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Question 1
Correct
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A 70-year-old man suffers an ischaemic stroke and develops a left homonymous hemianopia. Where is the likely infarct?
Your Answer: Right occipital lobe
Explanation:The man has a left homonymous hemianopia which means he is unable to view objects in the left visual field. This information is processed by the right primary visual cortex which lies in the right occipital lobe.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 2
Correct
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Lung compliance is increased by:
Your Answer: Emphysema
Explanation:Lung compliance is increased by emphysema, acute asthma and increasing age and decreased by alveolar oedema, pulmonary hypertension, atelectasis and pulmonary fibrosis.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 3
Correct
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Which statement is true regarding the diaphragmatic openings:
Your Answer: The thoracic duct passes through the opening at T12
Explanation:The diaphragmatic openings are:
T8 – opening for the inferior vena cavaand the right phrenic nerve
T10 – opening for the oesophagusand the left gastric artery and vein
T12 – opening for the aorta, the thoracic duct and azygos vein.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 4
Incorrect
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Which of the following is true about a patient who has undergone total colectomy and ileostomy?
Your Answer: This patient is at increased risk of anaemia due to malabsorption of vitamin B12
Correct Answer: Following total colectomy and ileostomy, the volume and water content of ileal discharge decreases over time
Explanation:After a patient has undergone total colectomy and ileostomy, the volume of ileal discharge, along with its water content gradually decreases over time. Post surgery, most patients can live a normal life. Iron and vitamin B12 absorption do not take place in the colon and hence are not affected significantly by a colectomy.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 5
Correct
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A 7-year-old boys undergoes a testicular biopsy after a tumour is found in his right testis. Elements similar to hair and teeth are found in it. What kind of tumour is this?
Your Answer: Teratoma
Explanation:A teratoma is a tumour containing tissue elements that are similar to normal derivatives of more than one germ layer. They usually contain skin, hair, teeth and bone tissue and are more common in children, behaving as a benign tumour. After puberty, they are regarded as malignant and can metastasise.
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This question is part of the following fields:
- Pathology
- Urology
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Question 6
Correct
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Calculate the stroke volume in a patient admitted for coronary bypass surgery, with the following parameters pre-operatively:
Oxygen consumption = 300 ml/min
Arterial oxygen content = 20 ml/100 ml blood
Pulmonary arterial oxygen content = 15 ml/100 ml blood and Heart rate = 100 beats/min.Your Answer: 60 ml
Explanation:By Fick’s principle, cardiac output can be calculated as follows: VO2 = CO × (CAO2– CVO2) where VO2= oxygen consumption, CO = cardiac output, CAO2 = arterial oxygen content and CvO2 = mixed venous oxygen content. Thus, in the given problem, 300 ml/min = CO × (20 – 15) ml/100 ml CO = 300 × 100/5 ml/min CO = 6000 ml/min. Also, cardiac output = stroke volume × heart rate. Thus, 6000 ml/min = stroke volume × 100 beats/min. Hence, stroke volume = 6000/100 ml/min which is 60 ml/min.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 7
Correct
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A 65 year old man with a history of diabetes and hypertension presented with a stroke a few months ago severely affecting his speech and movement in the right arm and leg. A cerebral angiogram revealed a middle cerebral artery occlusion. A recent CT scan was done which revealed a 5 cm cystic space in his left parietal lobe. This lesion is a result of which of the following forms of resolution?
Your Answer: Liquefactive necrosis
Explanation:Characteristically, the brain will undergo liquefactive necrosis following ischaemic injury. This leaves a cystic space in that region which would show up on a CT scan. Atrophy would result in a generalized decrease in the brain size. Coagulative necrosis typically occurs in parenchymal organs e.g. the spleen or kidney which have a lower lipid content. Caseous necrosis is typical in granulomatous tuberculosis infection. Apoptosis will not form a cystic area as it is programmed cell death involving a individual cells. Gangrenous necrosis is characteristic of ischaemic injury of the lower limb and GI tract. Fibrinous necrosis results from necrotic damage to the blood vessels with the leaking of proteins into the vessel, appearing bright pink on H & E staining.
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This question is part of the following fields:
- Cell Injury & Wound Healing; Neurology
- Pathology
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Question 8
Correct
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You observe a procedure to harvest the left internal thoracic (mammary) artery to be used as a graft for coronary artery bypass surgery. The left internal thoracic artery is mobilised from the inside of the chest wall and divided near the caudal end of the sternum. After dividing the internal thoracic artery at its distal end, the specialist registrar asks you to name the artery that will now have increased blood supply so that adequate blood flow is maintained to the rectus abdominis on the left side. What would your answer be?
Your Answer: Inferior epigastric artery
Explanation:The rectus abdominis muscle is supplied by the superior epigastric artery which is a branch of the internal thoracic artery. If the internal thoracic artery is thus ligated, blood would no longer flow to it. However, the superior epigastric artery communicates with the inferior epigastric artery (a branch of the external iliac artery). This means that blood could flow from the external iliac, to the inferior epigastric, to the superior epigastric to the rectus abdominis.
The superficial circumflex iliac artery and the superficial epigastric are two superficial branches of the femoral artery and do not supply the deep branches of the abdomen.
The deep circumflex iliac artery travels along the iliac crest on the inner surface of the abdominal wall; being too lateral it doesn’t supply blood to the rectus abdominis.
The distal portions of the umbilical arteries are obliterated in adults to form the medial umbilical folds.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 9
Correct
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A 55-year-old male chronic smoker is diagnosed with non-small-cell cancer. His right lung underwent complete atelectasis and he has a 7cm tumour involving the chest wall. What is the stage of the lung cancer of this patient?
Your Answer: T3
Explanation:Non-small-cell lung cancer is staged through TNM classification. The stage of this patient is T3 because based on the TNM classification the tumour is staged T3 if > 7 cm or one that directly invades any of the following: Chest wall (including superior sulcus tumours), diaphragm, phrenic nerve, mediastinal pleura, or parietal pericardium; or the tumour is in the main bronchus < 2 cm distal to the carina but without involvement of the carina, Or it is associated with atelectasis/obstructive pneumonitis of the entire lung or separate tumour nodule(s) in the same lobe.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 10
Incorrect
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Which of the following organelles have the capacity to regenerate and spontaneously replicate?
Your Answer: Vacuole
Correct Answer: Mitochondrion
Explanation:A mitochondria is a membrane bound organelle found in eukaryotic cells. They are called the powerhouse of the cell and are the place where ATP is formed from energy generated through metabolism. They are capable of replication as well as repair and regeneration.
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This question is part of the following fields:
- General
- Physiology
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Question 11
Incorrect
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The anatomical course of the phrenic nerve passes over the following muscle in the neck?
Your Answer: Sternocleidomastoid
Correct Answer: Anterior scalene
Explanation:The phrenic nerve originates in the neck between C3-C5, mostly C4 spinal root. It enters the thoracic cavity past the heart and lungs to the diaphragm. In the neck, this nerve begins at the lateral border of the anterior scalene muscle, its course then continues inferiorly on the anterior aspect of the anterior scalene muscle as it moves towards the diaphragm.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 12
Correct
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A football player sustained an injury to his ankle. The wound went through the skin, subcutaneous tissue and flexor retinaculum. Which other structure passing under the retinaculum may be injured?
Your Answer: Tibial nerve
Explanation:The flexor retinaculum is immediately posterior to the medial malleolus. The structures that pass under the flexor retinaculum from anterior to posterior are: tendon of the tibialis posterior, flexor digitorum longus, posterior tibial artery (and vein), tibial nerve and tendon of flexor hallucis longus. The tibial nerve is the only one which lies behind the flexor retinaculum.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 13
Correct
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Most of the coagulation factors are serine proteases. Which of the following is not one of them?
Your Answer: Factor XIII
Explanation:Serine protease coagulation factors include: thrombin, plasmin, Factors X, XI and XII. Factor VIII and factor V are glycoproteins and factor XIII is a transglutaminase.
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This question is part of the following fields:
- General
- Physiology
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Question 14
Correct
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When inserting a chest drain anteriorly into the second intercostal space, one must identify the second costal cartilage by palpating which landmark?
Your Answer: Sternal angle
Explanation:The sternal angle is the site for identification of the second rib as the second rib is attached to the sternum at this point.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 15
Incorrect
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A suspected recreational drug user was brought to the Emergency department in an unconscious state, and was found to be hypoventilating. Which of the following set of arterial blood gas analysis report is most consistent with hypoventilation as the primary cause? pH, pa(CO2) (mmHg), pa(O2) (mmHg).
Your Answer: 7.35, 50, 69
Correct Answer: 7.28, 55, 81
Explanation:Hypoventilation (or respiratory depression) causes an increase in carbon dioxide (hypercapnia) and respiratory acidosis. It can result due to drugs such as alcohol, benzodiazepines, barbiturates, opiates, mechanical conditions or holding ones breath. Strong opioids such as heroin and fentanyl are commonly implicated and can lead to respiratory arrest. In recreational drug overdose, acute respiratory acidosis occurs with an increase in p(CO2) over 45 mm Hg and acidaemia (pH < 7.35)
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 16
Correct
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Which organ is most vulnerable to haemorrhagic shock?
Your Answer: Kidneys
Explanation:At rest, the brain receives 15% cardiac output, muscles 15%, gastrointestinal tract 30% and kidneys receive 20%. However, if normalised by weight, the largest specific blood flow is received by the kidneys at rest (400 ml/min x 100g), making them highly vulnerable in the case of a haemorrhagic shock.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 17
Correct
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Which of the following is a fact worth noting about the development of the spleen?
Your Answer: It develops in the dorsal mesogastrium
Explanation:The spleen in the human embryo arises in week 5 of intrauterine life. It appears as a proliferating mesenchyme above the pancreas. The spleen is one the organs that develops in the dorsal mesogastrium. When the stomach changes its position during development, the spleen is made to move behind the stomach and stays in contact with the left kidney. The spleen is found within the peritoneum of the abdominal cavity thus it is an intraperitoneal organ.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 18
Incorrect
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A 58-year-old woman diagnosed with deep vein thrombosis had been using warfarin for 10 days. When she presented to the doctor she had haemorrhagic bullae and necrotic lesions in her lower limbs and buttocks. Deficiency of which of the following proteins may have caused the necrotic skin lesions?
Your Answer: Protein S
Correct Answer: Protein C
Explanation:Warfarin-induced skin necrosis is a rare complication of anticoagulant therapy that requires immediate drug cessation. The most common cutaneous findings include petechiae that progress to ecchymoses and haemorrhagic bullae. Warfarin inactivates vitamin K-dependent clotting factors II, VII, IX, and X and vitamin K-dependent proteins C and S. The concentration of protein C falls more rapidly than other vitamin K-dependent factors because they have a shorter half-lives. Skin necrosis is seen mainly in patients with prior protein C deficiency.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 19
Incorrect
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A 65-year old man, known with Type 2 diabetes and chronic renal failure, is likely to eventually present with which of the following conditions?
Your Answer: Cushing syndrome
Correct Answer: Secondary hyperparathyroidism
Explanation:When the parathyroid glands secrete excess parathyroid hormone (PTH) in response to hypocalcaemia, it is known as Secondary hyperparathyroidism and is often seen in patients with renal failure. In chronic renal failure, the kidneys fail to excrete adequate phosphorus and also fail to convert enough vitamin D to its active form. This leads to formation of insoluble calcium phosphate in the body which ultimately causes hypocalcaemia. The glands then undergo hyperplasia and hypertrophy leading to secondary hyperparathyroidism. Symptoms include bone and joint pains, along with limb deformities. The raised PTH also results in pleiotropic effects on blood, the immune system and nervous system.
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This question is part of the following fields:
- Endocrine
- Pathology
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Question 20
Correct
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A histological examination of a lump showed an abnormal amount and arrangement of normal tissue in an otherwise normal area. This condition is known as?
Your Answer: Hamartoma
Explanation:A hamartoma is a condition best described as tissue normally present in an area arranged haphazardly in an disorganized, abnormal fashion. They are never malignant and do not metastasis.
All the neoplastic, cancerous lesions comprise of a mixture of different cells that are not normal to that area.
Metaplasia is a change in the type of the epithelium.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 21
Correct
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A 19 year old male patient exhibiting signs of shock was brought to the casualty after he had fallen from the 3rd floor of a building. An examination carried out revealed tenderness on the left mid-posterior axillary line and low blood pressure. Further palpation revealed a large swelling that protruded downward and medially below the left costal margin. X-rays showed that the 9th and the 10th ribs were fractured near their angles. Considering these results, which abdominal organ was likely injured by the fractured ribs.
Your Answer: Spleen
Explanation:The spleen, left kidney, stomach, the splenic flexure of the colon and the suprarenal glands are all in the same quadrant- the left upper quadrant. However, the spleen is the most readily injured organ when there is fracture to the 10th, 11th and the 12th ribs because of its close association with these ribs. This patient exhibits a great indication of a ruptured spleen (tenderness on the left mid and posterior axillary line). The spleen is a thin capsulated organ with a spongy parenchyma, allowing it to bleed profusely in the event of injury. The liver, head of the pancreas and the duodenum are all in the right upper quadrant.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 22
Correct
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A 58-year-old woman has had a headache, fever, lethargy and nausea for the last 10 days. He undergoes a CT scan which reveals a lesion in his frontal lobe, which, after a biopsy, is found to be formed by granulation tissue with collagenisation, gliosis and oedema. What's the most likely diagnosis?
Your Answer: Chronic brain abscess
Explanation:A cerebral abscess can result from direct extension of cranial infections, penetrating head trauma, haematogenous spread, or for unknown causes. An abscess forms when an area of cerebral inflammation becomes necrotic and encapsulated by glial cells and fibroblasts. Oedema around the abscess can increase the intracranial pressure. Symptoms result from increased intracranial pressure and mass effects. In a CT scan, an abscess appears as an oedematous mass with ring enhancement.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 23
Incorrect
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Which nuclei of the posterior grey column of the spinal cord are likely affected in a patient who has lost the sensation of pain and temperature?
Your Answer: Nucleus proprius
Correct Answer: Substantia gelatinosa
Explanation:Substantia gelatinosa is one of the nuclei in the posterior grey column along side other posterior grey column nuclei like the nucleus dorsalis, nucleus proprius, and posteromarginal nucleus. These nuclei are a collection of cells in the posterior grey area found in throughout the spinal cord. The substantia gelatinosa receives direct input from the dorsal nerve roots (sensory), especially from thermoreceptors and nociceptors (receptors for temperature and pain).
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This question is part of the following fields:
- Anatomy
- Neurology
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Question 24
Correct
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A 35 year-old female developed food poisoning 24H after eating canned food. She complained of abdominal cramps, with nausea and vomiting. Shortly after she suddenly developed weakness, blurring of vision, difficulty in swallowing and breathing. Which of the following organisms is most likely associated with fatal food poisoning?
Your Answer: Clostridium botulinum
Explanation:C. botulinum is a Gram-positive, rod-shaped, spore-forming bacterium. It is an obligate anaerobe, meaning that oxygen is poisonous to the cells. Only botulinum toxin types A, B, E, and F cause disease in humans. Types A, B, and E are associated with foodborne illness. Botulism poisoning can occur due to preserved or home-canned, low-acid food that was not processed using correct preservation times and/or pressure. Signs and symptoms of foodborne botulism typically begin between 18 and 36 hours after the toxin gets into the body, but can range from a few hours to several days, depending on the amount of toxin ingested. Botulinum that is produced by Clostridium botulinum can cause respiratory and muscular paralysis.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 25
Incorrect
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During strenuous exercise, what else occurs besides tachycardia?
Your Answer: Increased renal blood flow
Correct Answer: Increased stroke volume
Explanation:During strenuous exercise there is an increase in:
– Heart rate, stroke volume and therefore cardiac output. (CO = HR x SV)
– Respiratory rate (hyperventilation) which will lead to a reduction in Paco2.
– Oxygen demand of skeletal muscle, therefore leading to a reduction in mixed venous blood oxygen concentration.
Renal blood flow is autoregulated, so renal blood flow is preserved and will tend to remain the same. Mean arterial blood pressure is a function of cardiac output and total peripheral resistance and will increase with exercise, mainly as a result of the increase in cardiac output that occurs.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 26
Incorrect
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During hysterectomy, the ureter is most likely to be ligated when a surgeon is clamping the?
Your Answer: Broad ligaments
Correct Answer: Uterine arteries
Explanation:The ureter forms the posterior boundary of a shallow depression which lodges the ovary and then runs medially and forward on the lateral aspect of the uterine cervix and upper part of the vagina to reach the fundus of the bladder. It is also situated about 2cm from the side of the cervix of the uterus. The relationship of the ureters and uterine arteries is of clinical significance because the arteries are at risk of iatrogenic injury during hysterectomy.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 27
Incorrect
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Injury of the ventral rami at this cervical spinal level will result in paralysis of the rectus capitis anterior muscle:
Your Answer: C1, C2, C3
Correct Answer: C1, C2
Explanation:The rectus capitis anterior is a short, flat muscle, situated immediately behind the upper part of the longus capitis. It is also known as the obliquus capitis superior. It aids in flexion of the head and the neck. Nerve supple is from C1 and C2.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 28
Correct
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A 45-year-old-female is suspected to have a pulmonary mass. Supposing that she has a neoplasm, which of the following are most commonly found to involve the lung:
Your Answer: Pulmonary metastases
Explanation:Lung metastases occur when a cancer started in another part of the body (primary site) spreads to the lungs. The lungs are among the most common site where cancer can spread due to its rich systemic venous drainage, almost every type of cancer can spread to the lung. The most common types of cancer that spread to the lung are breast, colorectal, kidney, testicular, bladder, prostate, head and neck cancers.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 29
Correct
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During a clinical rotation in the ENT clinic, you observe a flexible bronchoscopy. As the scope is passed down the trachea, you see a cartilaginous structure that resembles a ship's keel and separates the right and the left main stem bronchi. This structure is the:
Your Answer: Carina
Explanation:The carina (a keel-like cartilage) is found at the bifurcation of the trachea separating the right from the left main stem bronchi. It is a little more to the left than to the right.
The cricoid cartilage is the inferior and posterior cartilage of the larynx.
The costal cartilage on the other hand elongates the ribs anteriorly and contribute to the elasticity of the thoracic cage.
The pulmonary ligament is a fold of pleura located below the root of the lung.
Tracheal rings are rings of cartilage that support the trachea.
Peritracheal fascia is a layer of connective tissue that invests the trachea from the outside and is not visible on bronchoscopy.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 30
Correct
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In a cardiac cycle, what event does the closing of atrioventricular (AV) valves coincide with?
Your Answer: First heart sound
Explanation:In the cardiac cycle, the closing of the atrioventricular (AV) valves coincides with the onset of ventricular systole. This event marks the beginning of the isovolumetric contraction phase, where the ventricles begin to contract, but the volume of blood in the ventricles remains the same because both the AV valves and the semilunar valves (aortic and pulmonary valves) are closed. The closing of the AV valves produces the first heart sound, known as “S1” or “lub.”
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 31
Incorrect
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A histology report of a cervical biopsy taken from a patient with tuberculosis revealed the presence of epithelioid cells. What are these cells formed from?
Your Answer: Lymphocytes
Correct Answer: Macrophages
Explanation:Granulomas formed in tuberculosis are called tubercles and are made up polynuclear phagocytes, Langhans cells and epithelioid cells. Macrophages when enlarged, consist of abundant cytoplasm and have a tendency of arranging themselves very closely to each other representing epithelial cells. These enlarged macrophages are therefore termed as epithelioid cells.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 32
Correct
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Muscles and tendons in the planter region of the foot mainly take blood supply from:
Your Answer: Posterior tibial artery
Explanation:The posterior tibial artery is the main source of blood supply to the posterior compartment of the leg.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 33
Correct
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A young girl injured her arm following a fall down the steps On examination, it was found that her left proximal radioulnar joint had dislocated and the annular ligament was stretched. This will make which movement extremely painful?
Your Answer: Supination
Explanation:Supination is the rotation of the forearm so that the palm of the hand faces anteriorly. This is performed by the biceps brachii and supinator of the extensor muscles of the thumb. The opposite action of moving the palm from an anterior-facing position to a posterior-facing position is called pronation. Pronation is performed by the pronator teres and pronator quadratus.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 34
Correct
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A 72-year-old male presents with dysuria and chronic haematuria. He was diagnosed with bladder cancer and tumour invasion of the perivesical fat. What is the stage of the patient's bladder cancer?
Your Answer: T3
Explanation:Bladder cancer is the growth of abnormal or cancerous cells on the inner lining of the bladder wall. The staging is as follows; stage 0is (Tis, N0, M0): Cancerous cells in the inner lining tissue of the bladder only, stage I (T1, N0, M0): tumour has spread onto the bladder wall, stage II (T2, N0, M0): tumour has penetrated the inner wall and is present in muscle of the bladder wall, stage III (T3, N0, M0): tumour has spread through the bladder to fat around the bladder and stage IV: (T4, N0, M0): tumour has grown through the bladder wall and into the pelvic or abdominal wall. The stage of cancer in the case presented is T3 because of the invasion of perivesical fat.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 35
Correct
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After being admitted to the hospital, a 60-year-old man is administered sodium nitroprusside. Which class of drugs does nitroprusside belong to?
Your Answer: Vasodilators
Explanation:Sodium nitroprusside is a potent peripheral vasodilator that affects both arterioles and venules. It is often administered intravenously to patients who are experiencing a hypertensive emergency. It reduces both total peripheral resistance as well as venous return, so decreasing both preload and afterload. For this reason it can be used in severe cardiogenic heart failure where this combination of effects can act to increase cardiac output. It is administered by intravenous infusion. Onset is typically immediate and effects last for up to ten minutes. The duration of treatment should not exceed 72 hours.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 36
Correct
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Question 37
Correct
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A 66-year-old man complains of constant headaches. On physical examination, the only relevant sign is a dark brown mole located on left his arm which has grown in size over the years and is itchy and painful. A MRI of the brain revealed a solitary lesion at the grey-white junction in the right frontal lobe, without ring enhancement. This lesion is most likely to be:
Your Answer: Metastatic carcinoma
Explanation:The location of the mass at the grey–white junction is typical of a metastasis. The most frequent types of metastatic brain tumours originate in the lung, skin, kidney, breast and colon. These tumour cells reach the brain via the bloodstream. This patient is likely to have skin cancer, which caused the metastatic brain tumour.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 38
Correct
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During a procedure in the mediastinum, the surgeon accidentally injured a key structure that lies immediately anterior to the thoracic duct. Which structure is likely to be injured?
Your Answer: Oesophagus
Explanation:In the mid-thorax, the azygos vein, thoracic duct and aorta (in this order from right to the left) are all located posterior to the oesophagus. The superior vena cava, left internal jugular vein and trachea are not found in the mid thorax.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 39
Correct
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For calculation of cardiac output by Fick's principle, which of the following vessels is the best source of venous blood to determine the arterial-to-venous oxygen tension difference?
Your Answer: Pulmonary artery
Explanation:Fick’s principle states that the total uptake (or release) of a substance by peripheral tissues is equal to the product of the blood flow to the peripheral tissues and the arterial– venous concentration difference (gradient) of the substance. It is used to measure the cardiac output, and the formula is Cardiac output = oxygen consumption divided by arteriovenous oxygen difference. Assuming there are no shunts across the pulmonary system, the pulmonary blood flow equals the systemic blood flow. The arterial and venous blood oxygen content is measured by sampling from the pulmonary artery (low oxygen content) and pulmonary vein (high oxygen content). Peripheral arterial blood is used as a surrogate for the pulmonary vein.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 40
Correct
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A 49-year-old man, smoker, complains of a persisting and worsening cough over the past few months. He also has noted blood in his sputum. The patient has no other major health conditions. Which of the following investigative procedures should be done first?
Your Answer: Sputum cytology
Explanation:Sputum cytology is a diagnostic test used for the examination of sputum under a microscope to determine if abnormal cells are present. It may be used as the first diagnostic procedure to help detect a suspected lung cancer or certain non-cancerous lung conditions.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 41
Correct
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In multiple myeloma, which of these cell types confirms the diagnosis when found in a smear of bone marrow aspirate?
Your Answer: Plasma cells
Explanation:A bone marrow aspiration is the diagnostic test for multiple myeloma, which is a malignant bone tumour that usually affects older adults. The smear reveals clusters of plasma cells, while X-rays tend to show circumscribed lytic lesions or diffuse demineralisation.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 42
Correct
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A recognised side-effect of prefrontal leukotomy is:
Your Answer: Confusion
Explanation:Used previously as a treatment for psychiatric disorders, prefrontal leucotomy severs the connection between the prefrontal cortical association area and the thalamus. This leads to functional isolation of the prefrontal and orbitofrontal association cortex. Thus, along with the desired reduction in anger and frustration, undesirable side effects included changes in mood and affect, as well as confusion.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 43
Correct
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Which Statement is true of the brachial plexus?
Your Answer: The posterior cord continues as the axillary nerve
Explanation:The lateral cord continues as the musculocutaeous nerve.
The medial cord continues as the ulnar nerve.
The posterior cord continues as the radial nerve and the axillary nerve.
The nerve to subclavius muscle is a branch of the C6 root.
The suprascapular nerve is a branch from the upper trunk.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 44
Incorrect
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Medulloblastoma usually occurs in children between 5 to 9 years old. Where does medulloblastoma commonly originate from?
Your Answer: Pons
Correct Answer: Cerebellar vermis
Explanation:Medulloblastoma is the most common malignant brain tumour in children, accounting for 10-20% of primary CNS neoplasms. Most of the tumours originate in the cerebellar vermis.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 45
Incorrect
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A young man came to the emergency room after an accident. The anterior surface of his wrist was lacerated with loss of sensation over the thumb side of his palm. Which nerves have been damaged?
Your Answer: Radial
Correct Answer: Median
Explanation:The median nerve provides cutaneous innervation to the skin of the palmar radial three and a half fingers. Also the site of injury indicates that the medial nerve may have been injured as it passes into the hand by crossing over the anterior wrist.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 46
Incorrect
-
A 10-year-old boy was sent for an x-ray of the leg because he was complaining of pain and swelling. The x-ray showed the classic sign of Codman's triangle. What is the most likely diagnosis of this patient?
Your Answer: Osteomyelitis
Correct Answer: Osteosarcoma
Explanation:Codman’s triangle is the triangular area of new subperiosteal bone that is created when a lesion, often a tumour, raises the periosteum away from the bone. The main causes for this sign are osteosarcoma, Ewing’s sarcoma, eumycetoma, and a subperiosteal abscess.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 47
Correct
-
During a radical mastectomy for advanced breast cancer, the surgeon injured the long thoracic nerve. Which among the following muscles is likely to be affected?
Your Answer: Serratus anterior
Explanation:The long thoracic nerve innervates the serratus anterior muscle which holds the scapula forward and balances the rhomboids and the trapezius muscles which retract the scapula. Injury to this nerve results in a ‘winged scapula’ with a posterior protrusion.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 48
Incorrect
-
Regarding the venous drainage of the heart which of these is correct?
Your Answer: The middle and small cardiac veins drain most of the areas supplied by the left coronary artery
Correct Answer: The great cardiac vein is the largest tributary of the coronary sinus and this vein starts at the apex of the heart and ascends with the anterior ventricular branch of the left coronary artery
Explanation:Most of the veins of the heart open into the coronary sinus. This is a wide venous channel, about 2.25 cm in length, situated in the posterior part of the coronary sulcus and covered by muscular fibres from the left atrium. Its tributaries are the great, small and middle cardiac veins, the posterior vein of the left ventricle and the oblique vein of the left atrium. The great cardiac vein is the largest tributary of the coronary sinus.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 49
Correct
-
Hepatomegaly with greatly increased serum alpha-fetoprotein is seen in which of the following conditions?
Your Answer: Hepatocellular carcinoma
Explanation:Hepatocellular carcinoma or hepatoma affects people with pre-existing cirrhosis and is more common in areas with higher prevalence of hepatitis B and C. Diagnosis include raise alpha-fetoprotein levels, imaging and liver biopsy if needed. Patients at high-risk for developing this disease can undergo screening by periodic AFP measurement and abdominal ultrasonography. The malignancy carries poor prognosis (see also Answer to 10.4).
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 50
Correct
-
The physician suggested lifestyle modification for his patient because his present condition could increase his risk for the development of adenocarcinoma of the oesophagus. What is the most common predisposing factor for the development of adenocarcinoma of the oesophagus?
Your Answer: Gastro-oesophageal reflux disease
Explanation:Barret’s oesophagus is attributed primarily to gastro-oesophageal reflux disease. The chronic acidic environment damages the squamous epithelial lining of the oesophagus, and subsequently undifferentiated pluripotent stem cells develop into columnar epithelium, this is then known as Barret’s oesophagitis.
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This question is part of the following fields:
- Neoplasia
- Pathology
-
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Question 51
Correct
-
A 55-year old lady underwent a major surgery for repair of an aortic aneurysm. Her blood pressure was low throughout the intra-operative and the post-operative period, along with increasing serum creatinine and urea. Microscopic examination of her urine showed multiple granular and hyaline casts. What is the likely condition the patient is suffering from?
Your Answer: Acute tubular necrosis
Explanation:The most common predisposing factor leading to acute tubular necrosis is ischemia, typically seen in hospitalized patients with low blood pressure.
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This question is part of the following fields:
- Pathology
- Renal
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Question 52
Correct
-
Which lymph nodes are most likely to enlarge due to the spread of infection through the lymphatic channels in a patient with a boil on his scrotum?
Your Answer: Superficial inguinal nodes
Explanation:The superficial inguinal nodes drain the perineum and the external genitalia which include the scrotum and the labia majora. The testes, however, drain to the lumbar nodes.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 53
Correct
-
A 7-year-old girl is given cephalexin to treat an infection and develops hives, with localised facial oedema. Which of the following conditions will cause localised oedema?
Your Answer: Angio-oedema
Explanation:Angio-oedema, is the rapid swelling of the skin, mucosa and submucosal tissues. The underlying mechanism typically involves histamine or bradykinin. The version related to histamine is to due an allergic reaction to agents such as insect bites, food, or medications. The version related to bradykinin may occur due to an inherited C1 esterase inhibitor deficiency, medications e.g. angiotensin converting enzyme inhibitors, or a lymphoproliferative disorder.
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This question is part of the following fields:
- Physiology
- Renal
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Question 54
Incorrect
-
A 13-year-old boy's mother notices he has a lump in his arm, near his right shoulder. An X-ray reveals a lateral projection in the metaphyseal region of his humerus. The lesion is removed and it is found to be composed of bony cortex, capped by cartilage. What's the most likely diagnosis in this case?
Your Answer: Giant-cell tumour
Correct Answer: Osteochondroma
Explanation:Osteochondromas, or osteocartilaginous exostoses, are the most common benign bone tumours, and tend to appear near the ends of long bones. The overgrowth can occur in any bone where cartilage forms bone, and they are capped by cartilage. They are most common in people between the ages of 10-20 years old.
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This question is part of the following fields:
- Orthopaedics
- Pathology
-
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Question 55
Correct
-
During thyroidectomy, the recurrent laryngeal nerves are vulnerable to injury. Which of the following muscles will not be affected in cases where the recurrent laryngeal nerve is severed?
Your Answer: Cricothyroid
Explanation:All muscles of the larynx are supplied by the recurrent laryngeal nerve except for the cricothyroid which is supplied by the vagus nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 56
Correct
-
If the blood flow is constant, oxygen extraction by tissues will show the greatest decrease due to which of the following interventions?
Your Answer: Tissue cooling
Explanation:With a constant blood flow to a given tissue bed, there will be an increase in oxygen extraction by the tissue with the following; an increase in tissue metabolism and oxygen requirements: warming (or fever), exercise, catecholamines and thyroxine. With cooling, the demand for oxygen decreases, leading to decreased oxygen extraction.
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This question is part of the following fields:
- Cardiovascular
- Physiology
-
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Question 57
Correct
-
A 40-year old lady with a flail chest due to trauma was breathing with the help of a mechanical ventilator in the ICU, and was heavily sedated on muscle relaxants. Due to sudden power failure, a nurse began to hand-ventilate the patient with a Ambu bag. What change will occur in the following parameters: (Arterial p(CO2), pH) in the intervening period between power failure and hand ventilation?
Your Answer: Increase, Decrease
Explanation:Respiratory acidosis occurs due to alveolar hypoventilation which leads to increased arterial carbon dioxide concentration (p(CO2)). This in turn decreases the HCO3 –/p(CO2) and decreases pH. Respiratory acidosis can be acute or chronic. In acute respiratory acidosis, the p(CO2) is raised above the upper limit of normal (over 45 mm Hg) with low pH. However, in chronic cases, the raised p(CO2) is accompanied with a normal or near-normal pH due to renal compensation and an increased serum bicarbonate (HCO3 – > 30 mmHg). The given problem represents acute respiratory acidosis and thus, will show a increase in arterial p(CO2) and decrease in pH.
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This question is part of the following fields:
- Physiology
- Respiratory
-
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Question 58
Correct
-
Which of the following substances is most likely to cause pulmonary vasodilatation?
Your Answer: Nitric oxide
Explanation:In the body, nitric oxide is synthesised from arginine and oxygen by various nitric oxide synthase (NOS) enzymes and by sequential reduction of inorganic nitrate. The endothelium of blood vessels uses nitric oxide to signal the surrounding smooth muscle to relax, so dilating the artery and increasing blood flow. Nitric oxide/oxygen blends are used in critical care to promote capillary and pulmonary dilation to treat primary pulmonary hypertension in neonatal patients post-meconium aspiration and related to birth defects.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 59
Correct
-
What will the destruction of endoplasmic reticulum stop?
Your Answer: Synthesis of proteins
Explanation:The rough endoplasmic reticulum is the factory for the manufacturing of proteins. It contains ribosomes attached to it and transports proteins that are destined for membranes and secretions. The rough ER is connected to the nuclear envelope and to the cisternae of the Golgi apparatus by vesicles that shuttle between the two compartments.
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This question is part of the following fields:
- General
- Physiology
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Question 60
Correct
-
The dura mater is a thick membrane that is the outermost of the three layers of the meninges. Which of the following foramen transmits the dura mater?
Your Answer: Foramen magnum
Explanation:The foramen magnum is found in the most inferior part of the posterior cranial fossa . It is traversed by vital structures including the medulla oblongata . Its contents include the following: medulla oblongata, meninges (arachnoid, dura and pia mater), spinal root of the accessory nerve, vertebral arteries, anterior and posterior spinal arteries, tectorial membrane and alar ligaments .
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This question is part of the following fields:
- Anatomy
- Head & Neck
-
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Question 61
Correct
-
Injury to which of the following arteries is likely to affect the blood supply to the seminal vesicles?
Your Answer: Middle rectal
Explanation:Ligation of middle rectal artery is most likely to affect the blood supply of seminal vesicles since arteries supplying the seminal vesicles are derived from the middle and inferior vesical and middle rectal arteries.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 62
Correct
-
A cancer patient was found to have a radio resistant tumour. Which tumour does the patient most likely have?
Your Answer: Liposarcoma
Explanation:Liposarcoma is a cancer that arises in fat cells in deep soft tissue. Commonly it occurs inside the thigh or retroperitoneum. It usually affects middle-aged and older adults, over 40 years. Liposarcoma is the most common soft-tissue sarcoma. It is very radio resistant. Five-year survival rates vary from 100% to 56% based on histological subtype.
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This question is part of the following fields:
- Neoplasia
- Pathology
-
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Question 63
Correct
-
A 7-month-old abandoned baby with congenital non-communicating hydrocephalus is hosted by a clinic at its new-born hostel. A CT scan of the baby's brain reveals what might be a blockage of the ventricular system between the third and the fourth ventricles. Which of the following is the most likely blocked structure?
Your Answer: Cerebral aqueduct
Explanation:The drainage of cerebral spinal fluid from the third ventricle to the fourth ventricle is carried out by the cerebral aqueduct. The cerebral aqueduct is the narrowest passageway in the entire ventricular system and thus forms the most common site of blockage of flow of cerebrospinal fluid. The interventricular foramen allows passage of CSF to the third ventricle. The foramen of Luschka and Magendie are located on the fourth ventricle and allow passage of CSF to the subarachnoid space from the ventricular system. The pontine cistern is a space located on the ventral aspect of the pons. The cisterna magna is an opening on the subarachnoid space between the pia matter and the arachnoid.
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This question is part of the following fields:
- Anatomy
- Head & Neck
-
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Question 64
Incorrect
-
A week after a renal transplant the patient received antilymphocyte globulins. Shortly after she developed fever and hypotension. Which of the following mechanisms is involved in this response?
Your Answer: Type II hypersensitivity
Correct Answer: Type III hypersensitivity
Explanation:Type III hypersensitivity is characterized by soluble immune complexes which are aggregations of IgG and IgM antibodies with antigens that deposit in different tissues e.g. the skin, joints, kidneys. They can then trigger an immune response by activating the complement cascade. This reaction can take hours to develop and examples include: immuno-complex glomerulonephritis, rheumatoid arthritis, SLE, subacute bacterial endocarditis, arthus reaction and serum sickness.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 65
Correct
-
An old man presented with atrophy of the thenar eminence despite the sensation over it still being intact. What is the injured nerve in this case?
Your Answer: Median nerve
Explanation:Atrophy of the thenar muscles means injury to the motor supply of these muscles. The nerve that sends innervation to it is the median nerve. But the median nerve does not provide sensory innervation to the overlying skin so sensation is spared.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 66
Correct
-
Carbon dioxide is principally transported in the blood in which form?
Your Answer: Bicarbonate
Explanation:Carbon dioxide is transported in the blood in various forms:
– Bicarbonate (80–90%)
– Carbamino compounds (5–10%)
– Physically dissolved in solution (5%).
Carbon dioxide is carried on the haemoglobin molecule as carbamino-haemoglobin; carboxyhaemoglobin is the combination of haemoglobin with carbon monoxide.
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This question is part of the following fields:
- Physiology
- Respiratory; Cardiovascular
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Question 67
Correct
-
You are asked to help a junior medical student studying anatomy to identify the left lung. Which of the following features found only in the left lung will you use the identify it?
Your Answer: Cardiac notch
Explanation:Oblique fissure: is found on both the left and the right lungs. It separates the upper from the lower lobes in both lungs and the middle lobe from the lower lobe in the right lung(which has three lobes.)
The superior lobar bronchus is found in both lungs.
Cardiac notch: found only on the left lung.
Horizontal fissure: a deep groove separating the middle lobe from the upper lobe of the right lung is absent on the left lung.
Diaphragmatic surface: refers to the part of the lung, both the left and the right, that is in contact with the diaphragm.
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This question is part of the following fields:
- Anatomy
- Thorax
-
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Question 68
Correct
-
A space defined by the teres major muscle, the teres minor muscle, long head of the triceps brachii muscle and surgical neck of the humerus contains the axillary nerve and the?
Your Answer: Posterior circumflex humeral artery
Explanation:This quadrangular space transmits the posterior circumflex humeral vessels and the axillary nerve.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 69
Correct
-
What is the likely diagnosis in a 55-year old man presenting with jaundice, weight loss, pale coloured stools and elevated alkaline phosphatase?
Your Answer: Pancreatic carcinoma
Explanation:Increased alkaline phosphatase is indicative of cholestasis, with a 4x or greater increase seen 1-2 days after biliary obstruction. Its level can remain elevated several days after the obstruction is resolved due to the long half life (7 days). Increase up to three times the normal level can be seen in hepatitis, cirrhosis, space-occupying lesions and infiltrative disorders. Raised alkaline phosphatase with other liver function tests being normal can occur in focal hepatic lesions like abscesses or tumours, or in partial/intermittent biliary obstruction. However, alkaline phosphatase has several isoenzymes, which originate in different organs, particularly bone. An isolated rise can also be seen in malignancies (bronchogenic carcinoma, Hodgkin’s lymphoma), post-fatty meals (from the small intestine), in pregnancy (from the placenta), in growing children (from bone growth) and in chronic renal failure (from intestine and bone). One can differentiate between hepatic and non-hepatic cause by measurement of enzymes specific to the liver e.g. gamma-glutamyl transferase (GGT).
In an elderly, asymptomatic patient, isolated rise of alkaline phosphatase usually points to bone disease (like Paget’s disease). Presence of other symptoms such as jaundice, pale stools, weight loss suggests obstructive jaundice, most probably due to pancreatic carcinoma.
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 70
Correct
-
The posterior boundary of the carotid triangle is bounded by which of the following muscles?
Your Answer: Sternocleidomastoid
Explanation:The carotid triangle is a portion of the anterior triangle of the neck. It is bounded superiorly by the posterior belly of the digastric muscle, antero-inferiorly by the superior belly of omohyoid and posteriorly by the sternocleidomastoid. The floor is formed by the thyrohyoid, hyoglossus, middle and inferior pharyngeal constrictors and the roof is formed by the skin, superficial fascia, platysma and deep fascia.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 71
Correct
-
During an exploratory laparotomy of an acute abdomen, the surgeon identified an inflamed Meckel's diverticulum. This is:
Your Answer: Is a site of ectopic pancreatic tissue
Explanation:Meckel’s diverticulum is an outpouching of the small intestine. It usually occurs about 0.6 m (2 feet) before the junction with the caecum. It can be lined with the mucosa of the stomach and may ulcerate. It may also be lined by ectopic pancreatic tissue. It represents the remains of the vitelline duct in early fetal life.
An abnormal persistence of the urachus is called a urachal fistula.
Failure of the midgut loop to return to the abdominal cavity is called an omphalocele.
Polyhydramnios is often caused by anencephaly or oesophageal fistula.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 72
Correct
-
The patient who is diagnosed with bladder cancer asked his physician, what could have been the contributing factor in the development of his bladder cancer?
Your Answer: Smoking
Explanation:Tobacco smoking is the main known contributor to urinary bladder cancer. In most populations, smoking is associated with over half of bladder cancer cases in men and one-third of cases among women.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 73
Incorrect
-
A 30-year-old woman is diagnosed with Hodgkin's lymphoma. Which of the following chemotherapy regimens would be used in this case?
Your Answer: CHOP
Correct Answer: ABVD
Explanation:ABVD is a chemotherapy regimen used in the first-line treatment of Hodgkin’s lymphoma. It consists of concurrent treatment with the chemotherapy drugs, adriamycin, bleomycin, vinblastine and dacarbazine. It supplanted the older MOPP protocol.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 74
Correct
-
The histological exam of a tuberculous granuloma shows a periphery of multinuclear giant cells, with a central area of:
Your Answer: Caseous necrosis
Explanation:Granulomas with necrosis tend to have an infectious cause. The chronic infective lesion in this case typically presents with a central area of caseous (cheese-like) necrosis. Foam cells are the fat-laden M2 macrophages seen in atherosclerosis
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This question is part of the following fields:
- Cell Injury & Wound Healing; Dermatology
- Pathology
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Question 75
Correct
-
Which of the following can lead to haemolytic anaemia?
Your Answer: Presence of haemoglobin S
Explanation:Haemoglobin S is an abnormal type of haemoglobin seen in sickle cell anaemia. This allows for the haemoglobin to crystalize within the RBC upon exposure to low partial pressures of oxygen. This results in rupture of the RBCs as they pass through microcirculation, especially in the spleen. This can cause blockage of the vessel down stream and ischaemic death of tissues, accompanied by severe pain.
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This question is part of the following fields:
- General
- Physiology
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Question 76
Correct
-
An anatomy instructor is giving a demonstration of the right lung. Which of the statements about the right lung made by the demonstrator is correct?
Your Answer: Its upper lobar bronchus lies behind and above the right pulmonary artery
Explanation:The root of the lungs on both sides are similar in that the pulmonary veins are anterior and inferior while the bronchus is posterior. However, on the right side, the pulmonary arteries are anterior to the bronchus while on the left side the pulmonary arteries are superior to the bronchus. The lingual is only found on the left lung. The mediastinum is the space in the thorax between the two pleural sacs and does not contain any lung. The right lung, having three lobes, is slightly larger than the left lung. On both sides, the phrenic nerves passes in front of the root of the lung.
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This question is part of the following fields:
- Anatomy
- Thorax
-
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Question 77
Correct
-
A 30 year-old male patient sustained a sharp blow to the right side of the head, over the temporal region during a vehicular accident. This resulted to the rupture of the principal artery that supplies the meninges. Which artery is affected?
Your Answer: Middle meningeal artery
Explanation:The middle meningeal artery is typically the third branch of the first part of the maxillary artery, one of the two terminal branches of the external carotid artery. After branching off the maxillary artery in the infratemporal fossa, it runs through the foramen spinosum to supply the dura mater and the calvaria. The middle meningeal artery is the largest of the three (paired) arteries that supply the meninges, the others being the anterior meningeal artery and the posterior meningeal artery. The anterior branch of the middle meningeal artery runs beneath the pterion. It is vulnerable to injury at this point, where the skull is thin. Rupture of the artery may give rise to an epidural hematoma .An injured middle meningeal artery is the most common cause of an epidural hematoma.
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This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 78
Correct
-
Bile salt reuptake principally occurs where?
Your Answer: In the ileum
Explanation:90 – 95% of the bile salts are absorbed from the small intestine (mostly terminal ileum and then excreted again from the liver. This is known as the enterohepatic circulation. The entire pool recycles twice per meal and approximately 6 to 8 times per day.
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This question is part of the following fields:
- Gastroenterology
- Physiology
-
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Question 79
Incorrect
-
A 45 year-old male, with behavioural changes developed euvolemic hyponatraemia. Which of the following conditions most likely predisposed the patient to develop euvolemic hyponatraemia?
Your Answer: Protracted vomiting
Correct Answer: Psychosis
Explanation:In euvolemic hyponatraemia, there is volume expansion in the body, there is no oedema, but hyponatremia occurs. Causes include: state of severe pain or nausea, psychosis, brain trauma, SIADH, hypothyroidism and glucocorticoid deficiency.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
-
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Question 80
Correct
-
What principal artery that supplies the meninges is susceptible to rupture following trauma to the side of the head over the temporal region:
Your Answer: Middle meningeal artery
Explanation:The middle meningeal artery normally arises from the first or mandibular segment of the maxillary artery. The artery runs in a groove on the inside of the cranium, this can clearly be seen on a lateral skull X-ray. An injured middle meningeal artery is the most common cause of an epidural hematoma.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 81
Correct
-
Which of the following variables are needed to calculate inspiratory reserve volume of a patient?
Your Answer: Tidal volume, vital capacity and expiratory reserve volume
Explanation:Vital capacity = inspiratory reserve volume + tidal volume + expiratory reserve volume. Thus, inspiratory reserve volume can be calculated if tidal volume, vital capacity and expiratory reserve volume are known.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 82
Correct
-
A 40 year old man suffered severe trauma following a MVA. His BP is 72/30 mmhg, heart rate of 142 beats/mins and very feeble pulse. He was transfused 3 units of blood and his BP returned to 100/70 and his heart rate slowed to 90 beats/min. What decreased after transfusion?
Your Answer: Total peripheral resistance
Explanation:The patient is in hypovolemic shock, he is transfused with blood, this fluid resuscitation will result in a decreased sympathetic discharge and adequate ventricular filling which will result in the decreases TPR with an increased CO and cardiac filling pressures
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This question is part of the following fields:
- Cardiovascular
- Physiology
-
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Question 83
Correct
-
A neonate with failure to pass meconium is being evaluated. His abdomen is distended and X-ray films of the abdomen show markedly dilated small bowel and colon loops. The likely diagnosis is:
Your Answer: Aganglionosis in the rectum
Explanation:Hirschsprung’s disease (also known as aganglionic megacolon) leads to colon enlargement due to bowel obstruction by an aganglionic section of bowel that starts at the anus. A blockage is created by a lack of ganglion cells needed for peristalsis that move the stool. 1 in 5000 children suffer from this disease, with boys affected four times more commonly than girls. It develops in the fetus in early stages of pregnancy. Symptoms include not having a first bowel movement (meconium) within 48 hours of birth, repeated vomiting and a swollen abdomen. Two-third of cases are diagnosed within 3 months of birth. Some children may present with delayed toilet training and some might not show symptoms till early childhood. Diagnosis is by barium enema and rectal biopsy (showing lack of ganglion cells).
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This question is part of the following fields:
- Gastroenterology
- Physiology
-
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Question 84
Incorrect
-
All the following statements are FALSE regarding the ophthalmic division of the trigeminal nerve, except:
Your Answer: It follows the optic nerve and enters the bony orbit with it
Correct Answer: The ophthalmic nerve is the smallest branch of the trigeminal nerve
Explanation:The ophthalmic nerve is the smallest of the three trigeminal divisions. The cutaneous branches of the ophthalmic nerve supply the conjunctiva, the skin over the forehead, the upper eyelid, and much of the external surface of the nose.
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This question is part of the following fields:
- Anatomy
- Head & Neck
-
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Question 85
Correct
-
The principal motor and sensory nerve of the perineum is the?
Your Answer: Pudendal
Explanation:The pudendal nerve is formed by S1,2,4 anterior branches. It gives off the inferior haemorrhoid nerve before dividing terminally into the perineal nerve and the dorsal nerve of the clitoris or the penis. Thus, it is the principal motor and sensory nerve of the perineum.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 86
Correct
-
After having donated a unit of blood. The blood bank will prefer to use which of the following anticoagulants to store the blood?
Your Answer: Citrate
Explanation:Calcium is necessary for coagulation to occur. Citrate being a chelator and combining with calcium ions to form un-ionised compound will prevent coagulation. Following transfusion the citrate is removed by the liver with in a few minutes. Oxalate also works on the same principle but it is toxic to the body.
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This question is part of the following fields:
- General
- Physiology
-
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Question 87
Correct
-
One sensitive indicator of heavy alcohol dependence is:
Your Answer: Elevated serum gamma-glutamyl transpeptidase
Explanation:Elevated serum gamma-glutamyl transpeptidase (GGT) may be the only laboratory abnormality in patients who are dependent on alcohol. Heavy drinkers may also have an increased MCV.
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This question is part of the following fields:
- Hepatobiliary
- Physiology
-
-
Question 88
Correct
-
A 45-year-old woman was brought to the emergency department due to fever and chills. She has a history of recurrent UTI and complains of dysuria and urinary frequency. Urinary white blood cell count is >200 cell/high power field. If urine culture is performed, what is the most likely organism that will grow?
Your Answer: Escherichia coli
Explanation:The pathogen that most likely causes recurrent urinary tract infection in young women are E. coli, Enterococcus and Staphylococcus saprophyticus.
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This question is part of the following fields:
- Microbiology
- Pathology
-
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Question 89
Correct
-
An alcoholic patient was found to have hypomagnesaemia on blood tests. Which of the following clinical features will have prompted the doctor to check the serum magnesium level in this patient?
Your Answer: Seizures
Explanation:Hypomagnesaemia is a condition characterised by a low level of magnesium in the blood. The normal range for serum magnesium level is 0.75-1.05 mmol/l. In hypomagnesaemia serum levels of magnesium are less than 0.75 mmol/l. The cardiovascular and nervous systems are the most commonly affected. Neuromuscular manifestations include symptoms like tremor, tetany, weakness, apathy, delirium, a positive Chvostek and Trousseau sign, nystagmus and seizures. Cardiovascular manifestations include electrocardiographic abnormalities and arrhythmias e.g. ventricular fibrillation.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
-
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Question 90
Correct
-
Which of the following statements regarding the femoral artery is CORRECT?
Your Answer: It has the femoral nerve lying lateral to it
Explanation:The femoral artery begins immediately behind the inguinal ligament, midway between the anterior superior spine of the ilium and the symphysis pubis. The first 4 cm of the vessel is enclosed, together with the femoral vein, in a fibrous sheath (the femoral sheath). The femoral nerve lies lateral to this.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 91
Correct
-
During a normal respiratory exhalation, what is the recoil alveolar pressure?
Your Answer: +10 cmH2O
Explanation:To determine compliance of the respiratory system, changes in transmural pressures (in and out) immediately across the lung or chest cage (or both) are measured simultaneously with changes in lung or thoracic cavity volume. Changes in lung or thoracic cage volume are determined using a spirometer with transmural pressures measured by pressure transducers. For the lung alone, transmural pressure is calculated as the difference between alveolar (pA; inside) and intrapleural (ppl; outside) pressure. To calculate chest cage compliance, transmural pressure is ppl (inside) minus atmospheric pressure (pB; outside). For the combined lung–chest cage, transmural pressure or transpulmonary pressure is computed as pA – pB. pA pressure is determined by having the subject deeply inhale a measured volume of air from a spirometer. Under physiological conditions the transpulmonary or recoil pressure is always positive; intrapleural pressure is always negative and relatively large, while alveolar pressure moves from slightly negative to slightly positive as a person breathes.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 92
Correct
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Regarding the posterior compartment of the leg, which is correct?
Your Answer: The muscles plantarflex the foot and are innervated by the tibial nerve
Explanation:The muscles of the back of the leg are subdivided into two groups: superficial and deep. Superficial muscles include gastrocnemius, soleus and plantaris. Deep muscles include tibialis posterior, flexor hallucis longus, flexor digitorum longus and popliteus. The superficial ( calf muscles) which are responsible for plantarflexion of the foot are supplied by the tibial nerve as follows: the gastrocnemius and soleus muscles are supplied by the first and second sacral nerves and the plantaris by the fourth and fifth lumbar and first sacral nerve (the tibial nerve).
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 93
Incorrect
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The third branch of the maxillary artery lies in which fossa?
Your Answer: Infratemporal fossa
Correct Answer: Pterygopalatine fossa
Explanation:The maxillary artery supplies deep structures of the face. It branches from the external carotid artery just deep to the neck of the mandible. It is divided into three portions:
– The first or mandibular portion (or bony portion) passes horizontally forward, between the neck of the mandible and the sphenomandibular ligament.
– The second or pterygoid portion (or muscular portion) runs obliquely forward and upward under cover of the ramus of the mandible, on the surface of the lateral pterygoid muscle; it then passes between the two heads of origin of this muscle and enters the fossa.
– The third portion lies in the pterygopalatine fossa in relation to the pterygopalatine ganglion. This is considered the terminal branch of the maxillary artery. Branches from the third portion includes: the sphenopalatine artery, descending palatine artery, infraorbital artery, posterior superior alveolar artery, artery of pterygoid canal, pharyngeal artery, middle superior alveolar artery and anterior superior alveolar artery.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 94
Incorrect
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A 38-year old woman presents to the clinic with a 2 cm eczema-like lesion on the areolar region of her left breast, for 5 months. Biopsy of the lesion showed large cells at the dermal-epidermal junction with positive staining for mucin. What is the likely diagnosis?
Your Answer: Cystosarcoma phyllodes
Correct Answer: Paget’s disease of the breast
Explanation:Paget’s disease of the breast or nipple resembles eczema in appearance with an underlying carcinoma typically. The disease is usually unilateral and presents with inflammation, oozing and crusting along with a non-healing ulcer. Treatment is often delayed due to the innocuous appearance but can be fatal. It results due to spread of neoplastic cells from the ducts of the mammary gland to the epithelium.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 95
Incorrect
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A 78-year-old woman was brought to the emergency department with decreased consciousness, weakness and dehydration. Which serum electrolyte would most likely be low in this patient?
Your Answer: K+
Correct Answer: Na+
Explanation:Hyponatremia is a sodium level below 135 mEq/L. Signs and symptoms may include: nausea with vomiting, fatigue, headache or confusion, cramps or spasm, irritability and restlessness and severe cases may lead to seizures and comma.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 96
Correct
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A 40 year old patient with an history of obesity has been diagnosed with meralgia parasthetica. The condition was discovered to be caused by the pinching of the lateral femoral cutaneous nerve. Injuries at what spinal levels usually affect this nerve?
Your Answer: L2, L3
Explanation:The lateral femoral cutaneous nerve of the thigh arises from the dorsal division of the lumbar plexus of the second and the third lumbar nerves (L2 – L3). Spinal injuries at this level are likely to affect the lateral femoral cutaneous nerve. The lateral femoral cutaneous nerve innervates the skin on the lateral aspect of the thigh.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 97
Correct
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During an operation to repair an indirect inguinal hernia, it is noticed that the hernial sac is protruding out of the superficial inguinal ring. The superficial inguinal ring is an opening in which structure?
Your Answer: External abdominal oblique aponeurosis
Explanation:The superficial inguinal ring is an opening in the aponeurosis of the external oblique just above and lateral to the pubic crest. The opening is oblique and corresponds to the fibres of the aponeurosis. It is bound inferiorly by the pubic crest, on either side by the margins of the opening in the aponeurosis and superiorly by the curved intercrural fibres.
The inferior crus is formed by the portion of the inguinal ligament that is inserted into the pubic tubercle.
The falx inguinalis is made of arching fibres of the transversalis fascia and the internal abdominal oblique muscle. It forms the posterior wall of the inguinal canal.
The internal abdominal oblique forms the root of the inguinal canal.
Scarpa’s and Camper’s fascia are the membranous and fatty layers, respectively of subcutaneous fascia.
Transversalis fascia covers the posterior surface of the rectus abdominis muscle inferior to the arcuate line.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 98
Correct
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The specialist registrar, while performing the repair of an infrarenal abdominal aortic aneurysm, decides not to re-implant the inferior mesenteric artery into the repaired abdominal aorta. She says that an anastomotic artery running along the border of the large intestine is good enough to supply blood to the territory of the inferior mesenteric artery. Which vessel is she referring to?
Your Answer: Marginal
Explanation:The marginal artery is a key anastomosis for the large intestine that runs around the border of the large intestine and is formed by the anastomosis of the branches of the ileocolic artery, right colic artery, middle colic artery, left colic artery and sigmoid artery. If a small artery is occluded, these branches allow blood to reach all segments of the colon.
The arcades are anastomotic loops between the arteries that provide alternative pathways for blood flow. They are more prominent in the small intestine than the large intestine.
Arteriae rectae are small branches that run from the marginal artery to reach the colon.
The ileocolic artery is the branch of the superior mesenteric artery that supplies the caecum, appendix and terminal part of the ileum.
The coronary arteries supply blood to the heart.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 99
Correct
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The line which divides the perineum into two triangles is connected to the?
Your Answer: Ischial tuberosities
Explanation:The perineum has it’s deep boundaries in front of the pubic arch and the arcuate ligament of the pubis, behind the tip of the coccyx and on either side of the inferior rami of the pubis and ischium and the sacrotuberous ligament. It also corresponds to the outlet of the pelvis. A line drawn transversely across, in front of the ischial tuberosities divides the space into two portions, the posterior contains the termination of the anal canal and the anterior, contains the external urogenital organs.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 100
Incorrect
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Which of the following coagulation factors is responsible for the formation of a complex with tissue factor to activate factors IX and X?
Your Answer: Prothrombin
Correct Answer: Factor VII
Explanation:Factor VII, also known as proconvertin or stable factor, is a vitamin K–dependent protein that plays a central role in haemostasis and coagulation. Tissue factor is a protein that is normally not exposed on the surface of intact blood vessels. Damage to the vascular lumen leads to tissue factor exposure. The exposed tissue factor binds to factor VII. This facilitates the activation of factor VII to factor VIIa.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 101
Correct
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In which of the following conditions will the oxygen-haemoglobin dissociation curve shift to the right?
Your Answer: Exercise
Explanation:The oxygen-haemoglobin dissociation curve plots saturated haemoglobin against the oxygen tension and is usually a sigmoid plot. Each molecule of haemoglobin can bind to four molecules of oxygen reversibly. Factors that can influence the binding include: pH, concentration of 2,3-diphosphoglycerate (2,3-DPG), temperature, type of haemoglobin molecules, and presence of toxins, especially carbon monoxide. Shape of the curve is due to interaction of bound oxygen molecules with the incoming molecules. The binding of first molecule is difficult, with easier binding of the second and third molecule and increase in difficulty with the fourth molecule – partly as a result of crowding and partly as a natural tendency of oxygen to dissociate.
Left shift of curve indicates haemoglobin’s increased affinity for oxygen (seen at lungs). Right shift indicates decreased affinity and is seen with an increase in body temperature, hydrogen ions, 2,3-diphosphoglycerate (DPG), carbon dioxide concentration and exercise. Under normal resting conditions in a healthy individual, the normal position of the curve is at a pH of 7.4. A shift in the position of the curve with a change in pH is called the Bohr effect. Left shift occurs in acute alkalosis, decrease in p(CO2), decrease in temperature and decrease in 2,3-DPG. The fetal haemoglobin curve is to the left of the adult haemoglobin to allow for oxygen diffusion across the placenta. The curve for myoglobin is even further to the left. Carbon monoxide has a much higher affinity for haemoglobin than oxygen does. Thus, carbon monoxide poisoning leads to hypoxia.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 102
Correct
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One of the following structures is contained in the anterior compartment of the lower leg. Which is it?
Your Answer: Extensor hallucis muscle
Explanation:The lower leg is made up of four fascial compartments separated from one another by septa that contain the muscles of the lower leg. The four compartments are ; anterior, lateral, deep posterior and superficial posterior compartments.
These are the compartments and there contents:
i) Anterior compartment: Tibialis anterior muscle, extensor hallucis longus muscle, extensor digitorum longus muscle, peroneus tertius muscles, deep fibular nerve and anterior tibial blood vessels
ii) Lateral compartment: Fibularis longus muscle, brevis muscles and superficial fibular nerve
iii) Deep posterior compartment: Tibialis posterior m., flexor hallucis longus m., flexor digitorum longus m. ,popliteus m. , tibial nerve, posterior tibial artery and posterior tibial vessels such as the fibular artery.
iv) Superficial posterior compartment: Gastrocnemius m., soleus m., plantaris m., medial sural cutaneous nerve
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 103
Correct
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An experiment is carried out to observe engulfment and phagocytosis of microbes. Strep pneumoniae are added to a solution of leukocytes with a substance added to enhance the process of phagocytosis. What is this substance?
Your Answer: Complement C3b
Explanation:C3b is cleaved from C3 complement with the help of the enzyme C3- convertase. It binds to the cell surface of the offending substance and opsonizes it. This makes it easy for the phagocytes to detect and eliminate them.
IgM does not act as an opsonin but igG does.
Selectins aid leukocytes to bind to the endothelial surfaces.
C5a is a chemo-attractant and histamine a vasodilator.
NADPH oxidises offending substance after phagocytosis within the macrophage.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 104
Correct
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The gynaecologist suspects that her patient has a cervical cancer. What particular test should be done on this patient to screen for cervical cancer?
Your Answer: Pap smear
Explanation:Worldwide, approximately 500,000 new cases of cervical cancer and 274,000 deaths are attributable to cervical cancer yearly. This makes cervical cancer the second most common cause of death from cancer in women. The mainstay of cervical cancer screening has been the Papanicolaou test (Pap smear).
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 105
Incorrect
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A 47-year-old male smoker, who had been self-medicating with oral steroids for the last two years due to persistent breathlessness presented to the doctor complaining of a productive cough, fever and chest pain. A chest X-ray revealed bilateral patchy opacities. He was diagnosed with bilateral bronchopneumonia. Which of these organisms is most probably causing these findings?
Your Answer: Klebsiella pneumoniae
Correct Answer: Nocardia asteroides
Explanation:Nocardia is a Gram-positive aerobic actinomycete. Several species have been identified but the most common human pathogen is Nocardia asteroides. The predominant clinical finding in the majority of patients affected by nocardiosis is pulmonary disease. Predisposing factors for pulmonary nocardiosis include leukaemia, human immunodeficiency virus (HIV) infection, organ transplantation, diabetes and receiving prolonged corticosteroids.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 106
Correct
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A 50 year old man was admitted to the surgical ICU following a hemicolectomy for carcinoma of the caecum. A full blood count revealed: haematocrit = 30%, erythrocytes = 4 × 106/μ, haemoglobin level = 8 g/dl. To determine the likely cause of his anaemia, red blood cell indices were calculated. Which RBC indices are correct?
Your Answer: MCHC = haemoglobin concentration/haematocrit
Explanation:Mean corpuscular haemoglobin concentration (MCHC) is calculated simply by dividing the haemoglobin concentration (8 g/dl) by the haematocrit (0.3). The normal range is 31–36 g/dl. This patient has a hypochromic anaemia (MCHC = 8/0.3 = 26.7 g/dl). Dividing the haemoglobin concentration × 10 by erythrocyte number yields mean corpuscular haemoglobin (MCH). Normal range is 25.4–34.6 pg/cell and this patient has a significantly reduced cellular haemoglobin content (MCH = 8 × 10/4 = 20 pg/cell). Mean corpuscular volume (MCV) is calculated by dividing haematocrit × 1000 by erythrocyte number (4 × 106/μl). Normal range is 80–100 fl and this patient has a microcytic anaemia (MCV = 0.3 × 1000/4 = 75 fl). Microcytic, hypochromic anaemia is characteristic for iron-deficiency.
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This question is part of the following fields:
- General
- Physiology
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Question 107
Incorrect
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A 27 year old women works in a dry-cleaning shop. She was exposed to massive amounts of carbon tetrachloride on her skin as well as inhaled. Which of the following organs is most susceptible to damage?
Your Answer: Kidney
Correct Answer: Liver
Explanation:Carbon tetrachloride (CCl4) is a common agent used in the dry cleaning industry and is thought to cause the formation of free radicals. It causes rapid breakdown of the endoplasmic reticulum due to decomposition of lipids and severe liver cell injury. Within less than 30 mins, hepatic protein synthesis declines, lipid export is reduced due to lack of apoprotein and there is an influx of calcium and cell death.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 108
Correct
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A 55-year old patient with signs and symptoms of internal haemorrhage was brought in for emergency surgery to control the bleeding. Angiography results revealed an advanced duodenal tumour that had perforated the blood vessel immediately behind the first part of the duodenum. Which of the following is the most likely blood vessel that was ruptured by the cancer?
Your Answer: Gastroduodenal artery
Explanation:The gastroduodenal artery is the artery that lies just behind the first portion of the duodenum. The gastroduodenal artery would be the most likely artery to be perforated by a cancer in this area. The perforation is as a result of the spillage of the acidic content of the chyme in the duodenum. All the other blood vessels in the list would less likely be affected by the gastric expellant from the duodenum. The coronary vein is located in the lesser curvature of the stomach. The inferior pancreaticoduodenal arcade is located inferiorly to the first part of the duodenum on the head of the pancreas. The hepatic artery proper is a branch of the common hepatic artery that is located superior to the first portion of the duodenum. The splenic vein arises from the spleen; it forms the portal vein by joining the superior mesenteric vein. It is laterally detached from the duodenum. Both the left gastric vein and the splenic vein are located superior to the first portion of the duodenum.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 109
Incorrect
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What is the basic chemical reaction that takes place in the breakdown of complex foodstuffs?
Your Answer: Oxidation
Correct Answer: Hydrolysis
Explanation:Breakdown of complex food into simpler compounds is achieved by hydrolysis, with the help of different enzymes specific for different compounds.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 110
Incorrect
-
During a surgical operation, whilst dissecting the mediastinal lymph nodes for a bronchogenic carcinoma of the right upper lobe bronchus, a patient's right sympathetic trunk is accidentally severed above the level of spinal nerve T1. Which function would be left intact in the affected region?
Your Answer: Sweat production
Correct Answer: Voluntary muscle activity
Explanation:The sympathetic nervous system regulates vascular tone, dilation of pupils, arrector pili muscles, sweat production and visceral reflexes. Neurones that supply the voluntary muscles originate from the ventral horn of the spinal cord. If these nerves were thus damaged, these functions would be impaired. The sympathetic nervous system is not responsible for voluntary muscle activity.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 111
Correct
-
The ostium of the maxillary sinus opens into which of the following structures?
Your Answer: Middle meatus
Explanation:The maxillary sinuses usually develop symmetrically. The maxillary sinus ostium drains into the infundibulum which joins the hiatus semilunaris and drains into the middle meatus.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 112
Correct
-
In the human body, veins often run a course parallel to the artery that has the same name. Which of the following listed veins doesn't run parallel to the artery of the same name?
Your Answer: Inferior mesenteric
Explanation:The inferior mesenteric artery and inferior mesenteric vein don’t run in tandem because the vein is part of the portal venous system-draining into the splenic vein which drains into the hepatic portal vein. The inferior mesenteric artery is a branch of the descending aorta at the level of L3. The inferior mesenteric vein and artery, however, drain the same region i.e. the descending and sigmoid colon and rectum.
Superior epigastric vessels course together and are the continuation of the internal thoracic artery and vein.
Superficial circumflex iliac vessels course together in the superficial fat of the abdominal wall.
Superior rectal vessels are the terminal ends of the inferior mesenteric vessels, located on the posterior surface of the rectum.
The ileocolic artery and vein are branches off the superior mesenteric vessels. Both course in the mesentery, supplying/draining the caecum, appendix, terminal portion of the ileum. The inferior epigastric vessels run together.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 113
Correct
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Which of these laboratory findings will indicate a fetal neural tube defect when done between 15 and 20 weeks of pregnancy?
Your Answer: Increased alpha-fetoprotein
Explanation:Maternal serum screening during the second trimester is a non-invasive way of identifying women at increased risk of having children with a neural tube defect and should be offered to all pregnant women. The results are most accurate when the sample is taken between 15 and 20 weeks of gestation. Elevated levels of alpha-fetoprotein suggest open spina bifida, anencephaly, risk of pregnancy complications, or multiple pregnancy.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 114
Incorrect
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A 17-year-old female was given an antibiotic for a urinary tract infection. After taking the medication the patient developed Steven-Johnson syndrome. Which particular antibiotic usually causes Steven-Johnson syndrome?
Your Answer: Tetracycline
Correct Answer: Sulphonamides
Explanation:Stevens–Johnson syndrome (SJS) is a type of severe skin reaction. The most common cause is certain medications such as lamotrigine, carbamazepine, allopurinol, sulphonamide antibiotics, and nevirapine.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 115
Incorrect
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Which of the following physiological changes will you see in a young man who has been trekking in the Himalayas for 3 years?
Your Answer: Decreased haematocrit
Correct Answer: Increased renal excretion of HCO3 –
Explanation:The atmospheric pressure is lower at high altitudes as compared with sea level. This leads to a decrease in the partial pressure of oxygen. Once 2100 m (7000 feet) of altitude is reached, there is a drop in saturation of oxyhaemoglobin. The oxygen saturation of haemoglobin determines the oxygen content in the blood. The body physiological tries to adapt to high altitude by acclimatization. Immediate effects include hyperventilation, fluid loss (due to a decreased thirst drive), increase in heart rate and slightly lowered stroke volume. Long term effects include lower lactate production, compensatory alkali loss in urine, decrease in plasma volume, increased erythropoietin release and red cell mass, increased haematocrit, higher concentration of capillaries in striated muscle tissue, increase in myoglobin, increase in mitochondria, increase in aerobic enzyme concentration such as 2,3-DPG and pulmonary vasoconstriction.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 116
Correct
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What is correct regarding the obturator artery?
Your Answer: It is found in the medial compartment of the thigh
Explanation:The obturator artery is a branch of the internal iliac artery, which passes antero-inferiorly on the lateral wall of the pelvis, to the upper part of the obturator foramen. The posterior branch follows the posterior margin of the foramen and turns forward on the inferior ramus of the ischium. It also supplies an articular branch, which enters the hip joint through the acetabular notch, sending a branch along the ligamentum teres to the head of the femur. It is the main source of arterial supply to the medial compartment of the thigh
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 117
Correct
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Linezolid is an antibiotic used for the treatment of infections caused by bacteria that are resistant to other antibiotics. Which of the following organisms is most likely to be effectively treated by linezolid?
Your Answer: Methicillin-resistant Staphylococcus aureus
Explanation:Linezolid is a synthetic antibiotic used for the treatment of infections caused by multiresistant bacteria, including streptococci and methicillin-resistant Staphylococcus aureus (MRSA). Linezolid is effective against Gram-positive pathogens, notably Enterococcus faecium, S. aureus, Streptococcus agalactiae, Streptococcus pneumoniae and Streptococcus pyogenes. It has almost no effect on Gram-negative bacteria and is only bacteriostatic against most enterococci.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 118
Incorrect
-
After finding elevated PSA levels, a 69-year-old man undergoes a needle biopsy and is diagnosed with prostatic cancer. What is the stage of this primary tumour?
Your Answer: T1b
Correct Answer: T1c
Explanation:The AJCC uses a TNM system to stage prostatic cancer, with categories for the primary tumour, regional lymph nodes and distant metastases:
TX: cannot evaluate the primary tumour T0: no evidence of tumour
T1: tumour present, but not detectable clinically or with imaging T1a: tumour was incidentally found in less than 5% of prostate tissue resected (for other reasons)
T1b: tumour was incidentally found in more than 5% of prostate tissue resected
T1c: tumour was found in a needle biopsy performed due to an elevated serum prostate-specific antigen
T2: the tumour can be felt (palpated) on examination, but has not spread outside the prostate
T2a: the tumour is in half or less than half of one of the prostate gland’s two lobes
T2b: the tumour is in more than half of one lobe, but not both
T2c: the tumour is in both lobes
T3: the tumour has spread through the prostatic capsule (if it is only part-way through, it is still T2)
T3a: the tumour has spread through the capsule on one or both sides
T3b: the tumour has invaded one or both seminal vesicles
T4: the tumour has invaded other nearby structures.
In this case, the tumour has a T1c stage.
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This question is part of the following fields:
- Pathology
- Urology
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Question 119
Incorrect
-
Injury to this nerve will affect the function of the palatoglossus and levator veli palatini muscles:
Your Answer: Cranial nerve V
Correct Answer: Cranial nerve X
Explanation:The vagus nerve (cranial nerve X) innervates both the palatoglossus and levator veli palatini muscles.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 120
Correct
-
Which of the following arteries, that runs on the superior aspect of the first part of the duodenum, forms the lower boundary of the epiploic foramen (also known as the foramen of Winslow)?
Your Answer: Hepatic
Explanation:The epiploic foramen is an important anatomical opening that allows for the communication between the greater peritoneal sac and the lesser peritoneal sac. Its boundaries are formed; superiorly by the caudate lobe of the liver, anteriorly by the hepatoduodenal ligament (containing the components of the portal triad), inferiorly by the first part of the duodenum and posteriorly by the peritoneum covering the inferior vena cava. The superior aspect of the first part of the duodenum, which forms the inferior boundary of the foramen of Winslow, forms the course of the hepatic artery before it ascends to the porta hepatis where it divides into its right and left branches.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 121
Correct
-
During cardiac catheterisation in a 20-year old man, the following data is obtained: Pressure (mmHg), O2 saturation (%) Right atrium 7 (N = 5) 90 (N = 75), Right ventricle 35/7 (N = 25/5) 90 (N = 75), Pulmonary artery 35/8 (N = 25/15), 90 (N = 75), Left atrium 7 (N = 9) 95 (N = 95), Left ventricle 110/7 (N = 110/9) 95 (N = 95), Aorta 110/75 (N = 110/75) 95 (N = 95) where N = Normal value. What is the likely diagnosis?
Your Answer: Atrial septal defect
Explanation:A congenital heart disease, ASD or atrial septal defect leads to a communication between the right and left atria due to a defect in the interatrial septum. This leads to mixing of arterial and venous blood from the right and left side of the heart. The hemodynamic significance of this defect depends on the presence of shunting of blood. Normally, the left side of the heart has higher pressure than the right as the left side has to pump blood throughout the body. A large ASD (> 9 mm) will result in a clinically significant left-to-right shunt, causing volume overload of the right atrium and ventricle, eventually leading to heart failure. Cardiac catheterization would reveal very high oxygen saturation in the right atrium, right ventricle and pulmonary artery. Eventually, the left-to-right shunt will lead to pulmonary hypertension and increased afterload in the right ventricle, along with the increased preload due to the shunted blood. This will either cause right ventricular failure, or raise the pressure in the right side of the heart to equal or more than that in the left. Elevation of right atrial pressure to that of left atrial pressure would thus lead to diminishing or complete cessation of the shunt. If left uncorrected, there will be reversal of the shunt, known as Eisenmenger syndrome, resulting in clinical signs of cyanosis as the oxygen-poor blood form right side of the heart will mix with the blood in left side and reach the peripheral vascular system.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 122
Incorrect
-
A 42-year old woman presents to the doctor with jaundice. Her investigations show conjugated hyperbilirubinemia, raised urine bilirubin levels and low urine urobilinogen levels. What is the likely cause of her jaundice?
Your Answer: Haemolytic anaemia
Correct Answer: Blockage of the common bile duct
Explanation:The description of the patient here fits the diagnosis of obstructive jaundice or cholestasis, which results in conjugated hyperbilirubinemia. Cholestasis occurs due to impairment of bile flow, which can be anywhere from the liver cell canaliculus to the ampulla of Vater. Causes can be divided into intrahepatic and extrahepatic.
– Intrahepatic causes include hepatitis, drug toxicity, alcoholic liver disease, primary biliary cirrhosis, cholestasis of pregnancy and metastatic cancer.
– Extrahepatic causes include common duct stone, pancreatic cancer, benign stricture of the common duct, ductal carcinoma, pancreatitis and sclerosing cholangitis.
There is absence of bile constituents in the intestine, which causes spillage in the systemic circulation. Symptoms include pale stools, dark urine, pruritus, malabsorption leading to steatorrhea and deficiency of fat-soluble vitamins. Chronic cases can result in osteoporosis or osteomalacia due to vitamin D deficiency and Ca2+ malabsorption. Cholesterol and phospholipid retention produces hyperlipidaemia despite fat malabsorption (although increased liver synthesis and decreased plasma esterification of cholesterol also contribute); triglyceride levels are largely unaffected. The lipids circulate as a unique, low-density lipoprotein called lipoprotein X.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 123
Correct
-
A surgeon performing a thymectomy to remove a malignant thymoma is careful to avoid damaging an important nerve lying around the arch of the aorta. Which nerve is the surgeon trying to preserve?
Your Answer: Left Vagus
Explanation:The left vagus nerve lies on the lateral surface of the aortic arch. The left recurrent laryngeal nerve arises from the vagus and loops around the arch of the aorta. This nerve is at risk of injury during surgery.
The right and left phrenic nerves, being lateral to the vagus, do not loop around the arch of the aorta.
The sympathetic trunks, both right and left, are located in the posterior chest; not near the aortic arch.
The right vagus: not involved with the aortic arch.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 124
Correct
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A lad involved in a road traffic accident is rushed to casualty where physical examination reveals that he has limited extension of his right humerus. Which of the following nerves is most likely to have been injured?
Your Answer: Thoracodorsal nerve
Explanation:Extension of the humerus is a function of the latissimus dorsi. This muscle is supplied by the thoracodorsal nerve which is a branch of the posterior cord of the plexus whose fibres are derived from cranial nerves V, VI and VII.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 125
Correct
-
The following structures DO NOT lie between the layers of the mesosalpinx except for the?
Your Answer: Fallopian tube
Explanation:Mesosalpinx is the portion of the broad ligament that stretches from the fallopian tube to the ovary and contains the uterine tubes between it’s layers.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 126
Incorrect
-
A patient in the intensive care unit developed hyperphosphatemia. The phosphate level is 160 mmol/L. Which of the following is most likely responsible for this abnormality?
Your Answer: Refeeding after prolonged malnutrition
Correct Answer: Renal insufficiency
Explanation:Hyperphosphatemia is an electrolyte disturbance in which there is an abnormally elevated level of phosphate in the blood. It is caused by conditions that impair renal phosphate excretion (ex: renal insufficiency, hypoparathyroidism, parathyroid suppression) and conditions with massive extracellular fluid phosphate loads (ex: rapid administration of exogenous phosphate, extensive cellular injury or necrosis, transcellular phosphate shifts).
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 127
Correct
-
A 45-year old male patient with a long history of alcoholism developed liver cirrhosis that has led to portal hypertension. Which of the following plexuses of veins is most likely dilated in this patient?
Your Answer: Haemorrhoidal plexus
Explanation:The haemorrhoidal plexus or also known as the rectal plexus is a venous plexus that surrounds the rectum. This venous plexus in males communicates anteriorly with the vesical plexus and uterovaginal plexus in females. This venous plexus forms a site of free communication between the portal and systemic venous systems. In the case of portal hypertension this plexus would most likely dilate due to the increased pressure.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 128
Incorrect
-
What's the nodal stage of a testicular seminoma if several lymph nodes between 2cm and 5cm are found?
Your Answer: N3
Correct Answer: N2
Explanation:According to the American Joint Committee on Cancer (AJCC) 2002 guidelines, the nodal staging of testicular seminoma is the following:
N0: no regional lymph node metastases
N1: metastasis with lymph nodes 2 cm or less in their greatest dimension or multiple lymph nodes, none more than 2 cm
N2: metastasis with lymph nodes greater than 2 cm but not greater than 5 cm in their greatest dimension, or multiple lymph nodes, any one mass greater than 2 cm, but not more than 5 cm
N3: metastasis with lymph nodes greater than 5 cm in their greatest dimension.
The patient in this case has N2 testicular seminoma. This TNM staging is extremely important because treatment options are decided depending on this classification.
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This question is part of the following fields:
- Pathology
- Urology
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Question 129
Incorrect
-
During an operation to repair an indirect inguinal hernia, you are asked to indicate the position of the deep inguinal ring. You indicate this as being:
Your Answer: Medial to the inferior epigastric artery
Correct Answer: Above the midpoint of the inguinal ligament
Explanation:The deep inguinal ring is near the midpoint of the inguinal ligament, below the anterior superior iliac spine. It is lateral to the inferior epigastric artery. The superficial ring, however, is found above the pubic tubercle. The supravesical fossa is the space between the median and medial umbilical folds.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 130
Correct
-
A 31-year-old woman is diagnosed with adrenal hyperplasia, and laboratory samples are taken to measure serum aldosterone and another substance. Which is most likely to be the other test that was prescribed to this patient?
Your Answer: Plasma renin
Explanation:The evaluation of a patient in whom hyperaldosteronism is first to determine that hyperaldosteronism is present (serum aldosterone) and, if it is present, to differentiate primary from secondary causes of hyperaldosteronism. The aldosterone-to-renin ratio (ARR) is the most sensitive means of differentiating primary from secondary causes of hyperaldosteronism as it is abnormally increased in primary hyperaldosteronism, and decreased or normal but with high renin levels in secondary hyperaldosteronism.
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This question is part of the following fields:
- Physiology
- Renal
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Question 131
Incorrect
-
A 14 year-old girl is found to have haemophilia B. What pathological problem does she have?
Your Answer: Deficiency of factor X
Correct Answer: Deficiency of factor IX
Explanation:Haemophilia B (also known as Christmas disease) is due to a deficiency in factor IX. Haemophilia A is due to a deficiency in factor VIII.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 132
Correct
-
Cyclophosphamide is used as a chemotherapy and immunosuppressant agent and is indicated in various diseases. One of the most severe complications of its use is cancer of the:
Your Answer: Urinary bladder
Explanation:Cyclophosphamide is used to treat various types of cancer and autoimmune disorders. The main use of cyclophosphamide is in combination with other chemotherapy agents in the treatment of lymphomas, some forms of leukaemia and some solid tumours. Side-effects include nausea and vomiting, bone marrow suppression, stomach ache, diarrhoea, darkening of the skin/nails, alopecia, lethargy, and haemorrhagic cystitis. Cyclophosphamide is itself carcinogenic, potentially causing transitional cell carcinoma of the bladder as a long-term complication.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 133
Incorrect
-
Cranial nerve XII, the hypoglossal nerve, innervates which one of the following muscles in the list?
Your Answer: Palatoglossus
Correct Answer: Hyoglossus
Explanation:The cranial nerve XII, hypoglossal nerve, innervates all the intrinsic and extrinsic muscles of the tongue except the palatoglossus. The muscles of the tongue innervated by this nerve include the extrinsic muscles; hyoglossus, styloglossus, genioglossus and the intrinsic muscles; superior longitudinal, inferior longitudinal, vertical and transverse muscles. The salpingopharyngeus, palatoglossus and the palatopharyngeus muscles are innervated by the vagus nerve. The stylopharyngeus muscle is innervated by the glossopharyngeal nerve (CN IX). The mylohyoid muscle is innervated by the inferior alveolar nerve, a branch of the mandibular nerve. Finally, the geniohyoid muscle is innervated by the olfactory nerve (CN I) via the hypoglossal nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 134
Correct
-
A blood sample from a patient with polycythaemia vera will show which of the following abnormalities?
Your Answer: High platelet count
Explanation:Polycythaemia is a condition that results in an increase in the total number of red blood cells (RBCs) in the blood. It can be due to a myeloproliferative syndrome, chronically low oxygen levels or rarely malignancy. In primary polycythaemia/ polycythaemia vera the increase is due to an abnormality in the bone marrow, resulting in increased RBCs, white blood cells (WBCs) and platelets. In secondary polycythaemia the increase occurs due to high levels of erythropoietin either artificially or naturally. The increase is about 6-8 million/cm3 of blood. A type of secondary polycythaemia is physiological polycythaemia where people living in high altitudes who are exposed to hypoxic conditions produce more erythropoietin as a compensatory mechanism for thin oxygen and low oxygen partial pressure.
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This question is part of the following fields:
- General
- Physiology
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Question 135
Incorrect
-
A 29-year-old pregnant woman suffering from hyperemesis gravidarum is prescribed metoclopramide. What is the mechanism of action of metoclopramide?
Your Answer: Serotonin antagonist
Correct Answer: Dopamine antagonist
Explanation:Metoclopramide is a potent dopamine-receptor antagonist with anti-emetic and prokinetic properties. It is therefore commonly used to treat nausea and vomiting, and to facilitate gastric emptying in patients with gastric stasis. The anti-emetic action of metoclopramide is due to its antagonist activity at D2 receptors in the chemoreceptor trigger zone (CTZ) in the central nervous system. Common adverse drug reactions associated with metoclopramide include restlessness (akathisia), and focal dystonia.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 136
Correct
-
Both the arytenoid muscles and the lateral cricoarytenoid muscles perform this action on the glottis:
Your Answer: Adduction
Explanation:Both the arytenoid and the cricoartenoid muscles close the glottis. The lateral cricoarytenoid muscles extend from the lateral cricoid cartilage to the muscular process of the arytenoid cartilage. By rotating the arytenoid cartilages medially, these muscles adduct the vocal cords and thereby close the rima glottidis. The arytenoid muscle adducts or approximates the arytenoid cartilages, and thus closes the aperture of the glottis.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 137
Incorrect
-
Which of the following abnormalities can be seen in patients with hypermagnesemia?
Your Answer: Generalised seizures
Correct Answer: Respiratory depression
Explanation:Hypermagnesemia is an electrolyte disturbance in which there is a high level of magnesium in the blood. It is defined as a level greater than 1.1 mmol/L. Symptoms include weakness, confusion, decreased breathing rate, and cardiac arrest.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 138
Correct
-
Endometrial hyperplasia is most likely to be associated with which of the following conditions?
Your Answer: Fibrothecoma
Explanation:A benign tumour arising from the ovarian stroma, fibrothecoma are bilateral in 10% cases. The thecoma component of the tumour can produce oestrogen leading to endometrial hyperplasia. The thecoma is rich in lipid content and is responsible for the yellowish appearance of the tumour. Meig’s syndrome is the presence of fibrothecoma with a right-sided hydrothorax.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 139
Incorrect
-
The renal cortex and medulla, if seen under the microscope, is lacking one of the following:
Your Answer: Fenestrated endothelium
Correct Answer: Squamous epithelium
Explanation:Capillaries, Henle’s loop, collecting ducts, Bertin columns and type IV collagen in glomerular basement membrane are all structures present in the renal cortex or medulla. The squamous epithelium is the only one that is lacking in both the renal cortex and medulla, because normally it is not found above the outer urethra.
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This question is part of the following fields:
- Pathology
- Renal
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Question 140
Correct
-
A teenage Somalian boy presents with a complaint of an enlarged lower jaw. His blood film shows blast cells and macrophages. Which virus is responsible for this?
Your Answer: Epstein–Barr virus
Explanation:Burkitt’s lymphoma is a type of non-Hodgkin’s lymphoma. Histologically it is characterised by a starry sky appearance due to numerous neoplastic macrophages which are required to clear the rapidly dividing tumour cells/blast cells. Burkitt’s lymphoma commonly affects the jaw bone, forming a huge tumour mass. It is associated with translocation of c-myc gene and has three types: 1) endemic/African type, 2)sporadic and 3)immunodeficiency-associated. The first type is strongly associated with EBV.
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This question is part of the following fields:
- General
- Physiology
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Question 141
Correct
-
The operating surgeon notices a structure lying alongside a herniated mass whilst repairing an indirect inguinal hernia in a female patient. Which structure could this be?
Your Answer: Round ligament of the uterus
Explanation:The main structure traversing the inguinal canal in women is the round ligament. In men, it is the spermatic cord.
The iliohypogastric nerve innervates the abdominal wall and runs between the transversus abdominis and internal oblique muscles before piercing the internal oblique at the anterior superior iliac spine to run between the internal and external obliques.
The inferior epigastric artery is between the peritoneum and the transversus abdominis creating the lateral umbilical fold.
The ovarian artery and the ovarian vein are branches from the descending aorta and inferior vena cava that supply the ovary in the pelvic cavity.
The pectineal ligament is a thick fascial layer over the pectineal line of the pubis. It doesn’t traverse the canal.
The broad ligament if found on the lateral sides of the uterus.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 142
Incorrect
-
A 40 year old woman, who is under anaesthesia for an elective procedure, received an antibiotic injection. She immediately developed a rash and her airway constricted raising the airway pressure. Which mechanism is responsible for this reaction?
Your Answer: Type III hypersensitivity
Correct Answer: Type I hypersensitivity
Explanation:Type I hypersensitivity reaction is an immediate reaction that occurs due to binding of the antigen with antibodies attached to mast cells in a previously sensitized person. It has an immediate phase, which is characterised by vasodilation, leakage of plasma, smooth muscle spasm, or glandular secretions. This manifests in about 5-30 min and usually resolves within 60 mins. The delayed phase follows after 24 hours and can persist up to several days. It is due to infiltration of eosinophils, neutrophils, basophils and CD4+ cells and leads to tissue destruction. The nature of the reaction varies according to the site. It can take the form of skin allergy, hives, allergic rhinitis, conjunctivitis, bronchial asthma or food allergy.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 143
Correct
-
A 59-year-old woman with hyperaldosteronism is prescribed a diuretic. Which of the following diuretics promotes diuresis by opposing the action of aldosterone?
Your Answer: Potassium-sparing diuretic
Explanation:The term potassium-sparing refers to an effect rather than a mechanism or location. Potassium-sparing diuretics act by either antagonising the action of aldosterone (spironolactone) or inhibiting Na+ reabsorption in the distal tubules (amiloride). This group of drugs is often used as adjunctive therapy, in combination with other drugs, for the management of chronic heart failure. Spironolactone, the first member of the class, is also used in the management of hyperaldosteronism (including Conn’s syndrome) and female hirsutism (due to additional antiandrogen actions).
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This question is part of the following fields:
- Physiology
- Renal
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Question 144
Correct
-
A 40 year old man sustained a fracture to the surgical neck of his left humerus. Which of the following arteries is suspected to be injured in this case?
Your Answer: Posterior humeral circumflex
Explanation:The posterior humeral circumflex artery arises from the axillary artery and runs with the axillary nerve through the quadrangular space which is bounded laterally by the surgical neck of the humerus. After winding around the surgical neck of the humerus, it is distributed to the deltoid muscle and the shoulder joint. Thus fractures in the surgical neck of the humerus could result in an injury to this artery.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 145
Correct
-
An intern is attempting to put in an arterial line in an ICU patients left foot. Which is the best site to feel for the pulsation of the dorsalis pedis artery in the foot?
Your Answer: Just lateral to the tendon of extensor hallucis longus
Explanation:The dorsalis pedis artery is the continuation of the anterior tibial artery. The pulse of the posterior tibial artery, which comes from the posterior compartment of the leg, may be felt behind the medial malleolus just lateral to the tendon of the extensor hallucis longus.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 146
Correct
-
A correct statement about the RECTUM:
Your Answer: It is an important anastomotic site for the portal and caval (systemic) venous systems
Explanation:The rectum is part of the gastrointestinal tract that is continuous above with the sigmoid colon and below with the anal canal. It contains both longitudinal and circular smooth muscles. These are supplied by the enteric nervous system. It is about 12 cm long. It has no sacculations comparable with those of the colon. It has three permanent transverse folds called the valves of Houston. The peritoneum is related to the upper two thirds of the rectum only whereas the lower part is not covered by peritoneum. It is supplied by the superior rectal (hemorrhoidal) branch of the inferior mesenteric artery and the median sacral artery that is a direct branch from the abdominal aorta. It is drained by veins that begin as a plexus that surround the anus. These veins form anastomoses with the portal system (portocaval anastomoses).
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 147
Correct
-
In which of the following situations will fat necrosis occur?
Your Answer: Trauma to the breast
Explanation:Fat necrosis is necrosis of adipose tissue with subsequent deposition of calcium, giving it a white chalky appearance. It is seen characteristically in trauma to the breast and the pancreas with subsequent involvement of the peripancreatic fat. In the breast it may present as a palpable mass with is usually painless or as an incidental finding on mammogram. Fatty acids are released from the traumatic tissue which combine with calcium in a process known as saponification, this is an example of dystrophic calcification in which calcium binds to dead tissue. The central focus is surrounded by macrophages and neutrophils initially, followed by proliferation of fibroblasts, neovascularization and lymphocytic migration to the site of the insult.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 148
Correct
-
Pain in the epigastric region occurring typically 2-3 hours after meals and causing the patient to wake up at night is characteristic of which of the following conditions?
Your Answer: Duodenal ulcer
Explanation:The description is typical for duodenal ulcers. There is no pain upon waking in the morning however it appears around mid-morning and is relieved by ingestion of food. The pain also often causes the patient to wake up at night.
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 149
Correct
-
Point of entry of the vagal trunk into the abdomen:
Your Answer: Oesophageal hiatus
Explanation:The oesophageal hiatus is located in the muscular part of the diaphragm a T10 and is above, in front and a little to the left of the aortic hiatus. It transmits the oesophagus, the vagus nerves and some small oesophageal arteries.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 150
Correct
-
Which of the following is the most abundant WBC seen in a smear from a healthy person.
Your Answer: Neutrophils
Explanation:neutrophils are the most abundant cell type of the WBC. These phagocytes are found normally in the blood and increase in number are seen during an acute inflammation. These the percentages of WBC in blood Neutrophils: 40 to 60%
Lymphocytes: 20 to 40%
Monocytes: 2 to 8%
Eosinophils: 1 to 4%
Basophils: 0.5 to 1%
Band (young neutrophil): 0 to 3%. eosinophils, basophils, neutrophils are known as granulocytes and monocytes and lymphocytes as agranulocytes.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 151
Correct
-
The most likely cause of prominent U waves on the electrocardiogram (ECG) of a patient is:
Your Answer: Hypokalaemia
Explanation:The U-wave, not always visible in ECGs, is thought to represent repolarisation of papillary muscles or Purkinje fibres. When seen, it is very small and occurs after the T-wave. Inverted U-waves indicate myocardial ischaemia or left ventricular volume overload. Prominent U-waves are most commonly seen in hypokalaemia. Other causes include hypercalcaemia, thyrotoxicosis, digitalis exposure, adrenaline and class 1A and 3 anti-arrhythmic agents. It can also be seen in congenital long-QT syndrome and in intracranial haemorrhage.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 152
Incorrect
-
Which of the cranial nerves is responsible for touch sensation on the skin over the maxilla region and the mandible?
Your Answer: Facial
Correct Answer: Trigeminal
Explanation:The sensation of the face is provided by the trigeminal nerve which is cranial nerve V. It is also responsible for other motor functions such as biting and chewing. The trigeminal nerve has three branches; the ophthalmic nerve (V1), the maxillary nerve((V2) and the mandibular nerve (V3). These three branches exit the skull through separate foramina, namely; the superior orbital fissure, the foramen rotundum and the foramen ovale respectively. The mnemonic for this is ‘Standing room only’. The sensory fibres of the maxillary nerve are distributed to the lower eyelid and cheek, the nares and upper lip, the upper teeth and gums, the nasal mucosa, the palate and roof of the pharynx, the maxillary, ethmoid and sphenoid sinuses, and parts of the meninges. The sensory fibres of the mandibular nerve are distributed to the lower lip, the lower teeth and gums, the floor of the mouth, the anterior two-thirds of the tongue, the chin and jaw (except the angle of the jaw, which is supplied by C2–C3), parts of the external ear, and parts of the meninges. The mandibular nerve carries touch/ position and pain/temperature sensation from the mouth. The sensory fibres of the ophthalmic nerve are distributed to the scalp and forehead, the upper eyelid, the conjunctiva and cornea of the eye, the nose (including the tip of the nose), the nasal mucosa, the frontal sinuses and parts of the meninges (the dura and blood vessels). The sensory fibres of the maxillary nerve are distributed to the lower eyelid and cheek, the nares and upper lip, the upper teeth and gums, the nasal mucosa, the palate and roof of the pharynx, the maxillary, ethmoid and sphenoid sinuses, and parts of the meninges.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 153
Incorrect
-
A man came to the hospital complaining of a sensation of pins and needles in the dorsum of the thumb and digits 1 and 2. On further examination they found that he had weakness in wrist dorsiflexion and finger extension. Which nerve do you think is injured in this case?
Your Answer: Median
Correct Answer: Radial
Explanation:The radial nerve can be injured in multiple sites along its course in the upper limb, and each site has its own presentation. The major complaint is wrist drop which if high above the elbow, can cause numbness of the forearm and hand. It can last for several days or weeks. The most common site of compression for the radial nerve is at the proximal forearm in the area of the supinator muscles.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 154
Correct
-
A 35 year-old man presents with high grade fever for 7 days after returning from a trip to India. He tested positive for widal test. What is the most likely organism that caused his fever?
Your Answer: Salmonella typhi
Explanation:Typhoid fever is caused by virulent bacteria called Salmonella typhi. Salmonella typhi spread through contaminated food or water and occasionally through direct contact with someone who is infected.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 155
Correct
-
The fundus of the stomach receives blood supply from the same artery as the greater curvature of the stomach. Which of the following arteries when ligated will disrupt blood supply to the fundus of the stomach through this artery?
Your Answer: Splenic
Explanation:The fundus of the stomach along with the greater curvature of the stomach receive blood supply from the short gastric artery. The short gastric artery arises from the end of the splenic artery. The ligation of the splenic artery therefore would cause a disruption of blood supply to the fundus of the stomach.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 156
Correct
-
Into which vein does the left and right inferior thyroid veins drain?
Your Answer: Brachiocephalic vein
Explanation:The brachiocephalic vein is formed by the confluence of the subclavian and internal jugular veins. In addition it receives drainage from: the left and right internal thoracic veins (also called internal mammary veins), left and right inferior thyroid veins and the left superior intercostal vein.
The superior thyroid veins and middle thyroid veins drain into the internal jugular vein. The right and left inferior thyroid veins to drain into their respective brachiocephalic veins (right and left). -
This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 157
Correct
-
the action of the semimembranosus muscle is:
Your Answer: Extension of the hip and flexion of the knee
Explanation:the semimembranosus is situated at the back and medial side of the thigh. It arises from the upper and outer impression on the tuberosity of the ischium, above and lateral to the biceps femoris and semitendinosus. It is inserted mainly into the horizontal groove on the posterior medial aspect of the medial condyle of the tibia. it flexes the knee and assists in extension of the hip.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 158
Correct
-
The otic ganglion receives its preganglionic sympathetic fibres from which of the following nerves?
Your Answer: Glossopharyngeal nerve
Explanation:The otic ganglion is a small (2–3 mm), oval shaped, flattened parasympathetic ganglion of a reddish-grey colour, located immediately below the foramen ovale in the infratemporal fossa and on the medial surface of the mandibular nerve. The preganglionic parasympathetic fibres originate in the inferior salivatory nucleus of the glossopharyngeal nerve. They leave the glossopharyngeal nerve by its tympanic branch and then pass via the tympanic plexus and the lesser petrosal nerve to the otic ganglion. Here, the fibres synapse, and the postganglionic fibres pass by communicating branches to the auriculotemporal nerve, which conveys them to the parotid gland. They produce vasodilator and secretomotor effects.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 159
Correct
-
The muscles of the superficial posterior compartment of the leg insert into the:
Your Answer: Calcaneus
Explanation:The muscles of the superficial posterior compartment of the leg form the characteristic ‘calf’ shape of the posterior leg and include the gastrocnemius, soleus and plantaris. The gastrocnemius and soleus together form a muscular mass which is occasionally described as the triceps surae; its tendon of insertion is the tendo calcaneus. The tendo calcaneus is the thickest and strongest in the body and together with the tendon of the plantaris muscle is inserted into the posterior part of the calcaneus.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 160
Incorrect
-
An ECG of a 30 year old woman revealed low voltage QRS complexes. This patient is most probably suffering from?
Your Answer: Atrial fibrillation
Correct Answer: Pericardial effusion
Explanation:The QRS complex is associated with current that results in the contraction of both the ventricles. As ventricles have more muscle mass than the atria, they result in a greater deflection on the ECG. The normal duration of a QRS complex is 10s. A wide and deep Q wave depicts myocardial infarction. Abnormalities in the QRS complex maybe indicative of a bundle block, ventricular tachycardia or hypertrophy of the ventricles. Low voltage QRS complexes are characteristic of pericarditis or a pericardial effusion.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 161
Correct
-
A 27-year old lady is shot in the chest. The bullet enters superior to the upper edge of the clavicle. She had difficulty in breathing which is interpreted by the A&E physician as a likely indicator of a collapsed lung. If that is the case, what portion of the pleura is most likely to have been punctured?
Your Answer: Cupola
Explanation:The cupola is part of the pleura that extends above the first rib into the root of the lung. Most likely to injured in a stab above the level of the clavicle.
Costodiaphragmatic recess: the lowest extent of the pleural sac.
Pulmonary ligament: is a fold of pleura located below the root of the lung.
Mediastinal pleura: part of the pleura that lines the mediastinal cavity.
Hilar reflection is the part of the pleura where the visceral pleura of the lung reflects to become continuous with the parietal pleura.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 162
Incorrect
-
In an anatomy demonstration, the instructor asked one of the medical students to pass his index finger inferior to the root of the left lung. The student notices that his finger is blocked by a structure. Which structure do you think is responsible for this?
Your Answer: Costodiaphragmatic recess
Correct Answer: Pulmonary ligament
Explanation:The pulmonary ligament is dual layer of pleura stretching from the inferior part of the hilar reflection toward the diaphragm.
The costodiaphragmatic recess is the cavity at the inferior border of the lung where the costal pleura becomes the diaphragmatic pleura.
The cupola: is part of the pleura that extends superiorly above the first rib and has no association with the root of the lung.
Inferior vena cava is located in the mediastinum, not near the root of the lung.
Left pulmonary veins being part of the root of the lung, would not block access to behind the lung. Costomediastinal recess is the part of the pleura where the costal pleura become the mediastinal pleura.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 163
Correct
-
Routine evaluation of a 38 year old gentleman showed a slightly lower arterial oxygen [pa(O2)] than the alveolar oxygen [pA(O2)]. This difference is:
Your Answer: Is normal and due to shunted blood
Explanation:Blood that bypasses the ventilated parts of lung and enters the arterial circulation directly is known as shunted blood. It happens in normal people due to mixing of arterial blood with bronchial and some myocardial venous blood (which drains into the left heart). Diffusion limitation and reaction velocity with haemoglobin are immeasurably small. CO2 unloading will not affect the difference between alveolar and arterial p(O2). A large VSD will result in much lower arterial O2 as compared to alveolar O2.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 164
Incorrect
-
Which of these conditions is mithramycin used for?
Your Answer: Organ transplantation
Correct Answer: Hypercalcaemia of malignancy
Explanation:Mithramycin or Plicamycin is a tricyclic pentaglycosidic antibiotic derived from Streptomyces strains. It inhibits RNA and protein synthesis by adhering to DNA. It is used as a fluorescent dye and as an antineoplastic agent. It is also used to reduce hypercalcaemia, especially caused by malignancy. Plicamycin is currently used in multiple areas of research, including cancer cell apoptosis and as a metastasis inhibitor.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 165
Correct
-
A patient admitted for esophagectomy showed low levels of the lightest plasma protein in terms of weight. Which of the following is the lightest plasma protein:
Your Answer: Albumin
Explanation:Albumin is the most abundant and the lightest of all the plasma proteins. It maintains osmotic pressure, transports unconjugated bilirubin, thyroid hormones, fatty acids, drugs and acts as a buffer for pH.
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This question is part of the following fields:
- General
- Physiology
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Question 166
Incorrect
-
Which of these nerves controls adduction of hand?
Your Answer: Radial nerve
Correct Answer: Ulnar nerve
Explanation:The adductors of the fingers are the palmer interossei. They are supplied by the ulnar nerve, which is a branch of the medical cord of the brachial plexus.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 167
Correct
-
Digital rectal examination of a 75-year old gentleman who presented to the surgical clinic with urinary retention revealed an enlarged, nodular prostate. PSA was found to be elevated, favouring the diagnosis of prostatic malignancy. Which of the given options is the most common malignant lesion affecting the prostate gland?
Your Answer: Adenocarcinoma
Explanation:Prostatic adenocarcinoma is the commonest solid malignancy and non-dermatological cancer in men above 50 years age. Increasing in incidence with age and the highest risk seen in the black population. About 75% of cases are seen in men over 65 years. Other tumours affecting the prostate include undifferentiated prostate cancer, squamous cell carcinoma, and ductal transitional carcinoma, but these occur less commonly. Sarcomas usually affect children. Hormones play a role in the aetiology of prostate adenocarcinoma unlike the other types. Intraepithelial neoplasia is considered a precursor of invasive malignancy.
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This question is part of the following fields:
- Pathology
- Urology
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Question 168
Correct
-
A 27-year-old woman has chronic low serum calcium levels. Which of the following conditions may be responsible for the hypocalcaemia in this patient?
Your Answer: Hypoparathyroidism
Explanation:Chronic hypocalcaemia is mostly seen in patients with hypoparathyroidism as a result of accidental removal or damage to parathyroid glands during thyroidectomy.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 169
Incorrect
-
During routine laboratory tests, a 66-year-old man is found to be suffering from hypercholesterolaemia and is prescribed atorvastatin. What is the mechanism of action of atorvastatin?
Your Answer: Inhibits lipoprotein lipase
Correct Answer: Inhibits cholesterol synthesis
Explanation:Atorvastatin is a member of the drug class of statins, used for lowering cholesterol. The mode of action of statins is inhibition of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase. This enzyme is needed by the body to make cholesterol. The primary uses of atorvastatin is for the treatment of dyslipidaemia and the prevention of cardiovascular disease.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 170
Correct
-
Which muscle in the neck divides the neck into two large triangles?
Your Answer: Sternocleidomastoid
Explanation:The sternocleidomastoid muscle is an important landmark in the neck as it divides the neck into two; anterior and posterior triangles. These triangles help in the location of the structures of the neck including the carotid artery, head and neck lymph nodes, accessory nerve and the brachial plexus. It originates from the manubrium and medial portion of the clavicle and inserts on the mastoid process of the temporal bone, superior nuchal line. The sternocleidomastoid receives blood supply from the occipital artery and the superior thyroid artery. It is innervated by the accessory nerve (motor) and cervical plexus (sensory).
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 171
Incorrect
-
Which of the following is the most likely cause of massive splenomegaly in a 35-year old gentleman?
Your Answer: Infectious mononucleosis
Correct Answer: Myelofibrosis
Explanation:Causes of massive splenomegaly include chronic myelogenous leukaemia, chronic lymphocytic leukaemia, lymphoma, hairy cell leukaemia, myelofibrosis, polycythaemia vera, sarcoidosis, Gaucher’s disease and malaria.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 172
Incorrect
-
Which of the following is a likely cause of jaundice?
Your Answer: Common bile duct obstruction if the serum amino transferases are elevated and alkaline phosphatase is low
Correct Answer: Hepatic disease if plasma albumin is low and serum aminotransferase elevations > 500 units
Explanation:Jaundice can occur due to any of the possible causes and treatment depends upon diagnosing the correct condition. Mild hyperbilirubinemia with normal levels of aminotransferase and alkaline phosphatase is often unconjugated (e.g., due to haemolysis or Gilbert’s syndrome rather than hepatobiliary disease). Moderate or severe hyperbilirubinemia along with increased urinary bilirubin (bilirubinuria), high alkaline phosphatase or aminotransferase levels suggest hepatobiliary disease. Hyperbilirubinemia produced by any hepatobiliary disease is largely conjugated. In this case, other blood tests include hepatitis serology for suspected hepatitis, prothrombin time (PT) or international normalised ratio (INR), albumin and globulin levels, and antimitochondrial antibody levels (suspected primary biliary cirrhosis). Low albumin and high globulin levels suggest chronic rather than acute liver disease. In cases where there is only a an elevation of alkaline phosphatase, γ-glutamyl transpeptidase (GGT) levels should be checked – the levels of which will be found high in hepatobiliary disease, but not in bone disorder which can also lead to elevated alkaline phosphatase levels. In diseases of hepatobiliary origin, aminotransferase elevations > 500 units suggest a hepatocellular cause, whereas disproportionate increases of alkaline phosphatase (e.g., alkaline phosphatase > 3 times normal and aminotransferase < 200 units) suggest cholestasis. Because hepatobiliary disease alone rarely causes bilirubin levels > 30 mg/dl, higher levels are suggestive of a combination of severe hepatobiliary disease and haemolysis or renal dysfunction. Imaging is best for diagnosing infiltrative and cholestatic causes of jaundice. Liver biopsy is rarely needed, but can be of use in intrahepatic cholestasis and in some types of hepatitis.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 173
Correct
-
A 40-year old lady presented to the hospital with fever and mental confusion for 1 week. On examination, she was found to have multiple petechiae all over her skin and mucosal surfaces. Blood investigations revealed low platelet count and raised urea and creatinine. A platelet transfusion was carried out, following which she succumbed to death. Autopsy revealed pink hyaline thrombi in myocardial arteries. What is the likely diagnosis?
Your Answer: Thrombotic thrombocytopenic purpura
Explanation:Hyaline thrombi are typically associated with thrombotic thrombocytopenic purpura (TTP), which is caused by non-immunological destruction of platelets. Platelet transfusion is contraindicated in TTP. Platelets and red blood cells also get damaged by loose strands of fibrin deposited in small vessels. Multiple organs start developing platelet-fibrin thrombi (bland thrombi with no vasculitis) typically at arteriocapillary junctions. This is known as ‘thrombotic microangiopathy’. Treatment consists of plasma exchange.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 174
Incorrect
-
Which of the given options best describes the metabolic changes which occur following a severe soft tissue injury sustained after a PVA?
Your Answer: Protein anabolism
Correct Answer: Mobilisation of fat stores
Explanation:The following metabolic responses occur following trauma as part of a coping mechanism for the additional stress. These include acid base changes (metabolic acidosis or alkalosis), decrease urine output and osmolality, reduced basal metabolic rate (BMR), gluconeogenesis with amino acid breakdown and shunting, hyponatraemia as a result of impaired functioning of sodium pumps, hypoxic injury, coagulopathies, decreased immunity, increase extracellular fluid and hypovolemic shock, increase permeability leading to oedema, break down and mobilization of fat reserves, pyrexia and reduced circulating levels of albumin.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 175
Incorrect
-
What are some of the derivatives of the second pharyngeal arch?
Your Answer: Stylopharyngeus muscle
Correct Answer: Stylohyoid muscle
Explanation:Also known as the hyoid arch, it forms the side and front of the neck. From its cartilage develops the styloid process, stylohyoid ligament and lesser cornu of the hyoid bone. The muscular derivatives include the muscles of facial expression, stapedius, stylohyoid and the posterior belly of the digastric. All these are innervated by cranial nerve VII but migrate into the area of the mandibular arch.
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This question is part of the following fields:
- Anatomy
- Embryology
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Question 176
Incorrect
-
A 35-year-old woman is in a comatose state following a traumatic head injury, and is receiving intravenous (IV) antibiotics and IV fluids containing saline and 5% dextrose. A serum biochemistry analysis is performed five days later which shows a low serum potassium level. This is most likely to be due to:
Your Answer: Aldosterone deficiency
Correct Answer: Nothing per oral regimen
Explanation:In this patient the cause for hypokalaemia is insufficient consumption of potassium as she is nil-per mouth with no intravenous supplementation. Parenteral nutrition has been used for comatose patients, although enteral feeding is usually preferable, and less prone to complications.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 177
Incorrect
-
A 16-year old boy was brought in an unconscious state to the emergency department. Clinical evaluation pointed in favour of acute adrenal insufficiency. On enquiry, it was revealed that he was suffering from a high grade fever 24 hours prior. On examination, extensive purpura were noted on his skin. The likely diagnosis is:
Your Answer: Amyloidosis
Correct Answer: Meningococcaemia
Explanation:Findings described are suggestive of Waterhouse-Friderichsen syndrome which develops secondary to meningococcaemia. The reported incidence of Addison’s disease is 4 in 100,000. It affects both sexes equally and is seen in all age groups. It tends to show clinical symptoms at the time of metabolic stress or trauma. The symptoms are precipitated by acute infections, trauma, surgery or sodium loss due to excessive perspiration.
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This question is part of the following fields:
- Endocrine
- Pathology
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Question 178
Correct
-
A 50 year old female patient with an history of chronic headache was scheduled for CT scan. If the CT scan revealed a tumour at the horn of the lateral ventricle, which of the following structures is most likely to be compressed by this tumour?
Your Answer: Fibres of the corpus callosum
Explanation:The ventricular system of the brain is made up of four ventricles namely; two lateral and a third and forth ventricle. The ventricles are the site of the development of the cerebrospinal fluid. The left and right lateral ventricles are located in each of the brain’s hemispheres. The roof of the lateral ventricles are made up of the fibres of the corpus callosum. This is the structure that would be compressed by the a tumour on the roof of the lateral ventricles.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 179
Correct
-
An abdominal aortogram shows occlusion of the inferior mesenteric artery. Which of the following segments of bowel is most likely to have preserved arterial supply?
Your Answer: Caecum
Explanation:The inferior mesenteric artery supplies blood to the end of the transverse colon and all distal structures in the gastrointestinal tract i.e. splenic flexure, descending colon, sigmoid colon and rectum would all be deprived of blood if it were occluded. The caecum receives blood from the superior mesenteric artery so it would not be affected.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 180
Correct
-
Congenital anomalies of genitourinary tract are more common than any other system. Which of the following anomalies carries the greatest risk of morbidity?
Your Answer: Bladder exstrophy
Explanation:Bladder exstrophy is the condition where the urinary bladder opens from the anterior aspect suprapubically. The mucosa of the bladder is continuous with the abdominal skin and there is separation of the pubic bones. The function of the upper urinary tract remains normal usually. Treatment consists of surgical reconstruction of the bladder and returning it to the pelvis. There can be a need for continent urinary diversion along with reconstruction of the genitals.
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This question is part of the following fields:
- Pathology
- Renal
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Question 181
Correct
-
Injury to the supraspinatus muscle will affect:
Your Answer: Initiation of abduction of the humerus
Explanation:This muscle arises from the medial two-thirds of the supraspinatus fossa and from the supraspinatus fascia. It is inserted into the highest impression on the greater tubercle of the humerus after passing over the upper part of the shoulder joint. It works with the deltoid to raise the arm from the side of the trunk and initiate abduction. It also assists in fixation of the head of the humerus in the glenoid cavity.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 182
Incorrect
-
A 35 year old patient presenting with haematemesis, heart burn and bloody stool was diagnosed with a duodenal ulcer that had eroded the gastroduodenal artery. The patient was then rushed into theatre for an emergency procedure to control the haemorrhage. If the surgeon decided to ligate the gastroduodenal artery at its origin, which of the following arteries would most likely experience retrograde blood flow from collateral sources as a result of the ligation?
Your Answer: Left gastric
Correct Answer: Right gastroepiploic
Explanation:In the stomach and around the duodenum, there are many arterial anastomoses. Ligation of the gastroduodenal artery would result in the retrograde flow of blood from the left gastroepiploic artery to the right gastroepiploic artery. The blood flows into the right gastroepiploic artery, a branch of the gastroduodenal artery from the left gastroepiploic artery that branches from the splenic artery. This retrograde blood flow is aimed at providing alternate blood flow to the greater curvature of the stomach.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 183
Correct
-
Injury to this nerve will result to the loss of general sensory innervation of the lacrimal gland:
Your Answer: Ophthalmic nerve
Explanation:The lacrimal glands are paired, almond-shaped exocrine glands, that secrete the aqueous layer of the tear film. The lacrimal nerve, derived from the ophthalmic nerve, supplies the sensory component of the lacrimal gland. The greater petrosal nerve, derived from the facial nerve, supplies the parasympathetic autonomic component of the lacrimal gland.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 184
Incorrect
-
Urine specific gravity allows the assessment of which of the following renal functions?
Your Answer: Filtration
Correct Answer: Concentration
Explanation:Concentrating ability of kidneys is assessed by measuring the urine specific gravity. Normal values of urine specific gravity fall between 1.002 and 1.030 g/ml.
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This question is part of the following fields:
- Pathology
- Renal
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Question 185
Incorrect
-
A 40-year old woman with portal hypertension has impaired venous drainage of the anal canal above the pectinate line. Thus, there might be an increase in blood flow downward to the systemic venous system via anastomoses with the inferior rectal vein. This is a tributary of?
Your Answer: Inferior mesenteric vein
Correct Answer: Internal pudendal vein
Explanation:The inferior rectal vein drains into the internal pudendal vein. In addition the external iliac vein is one of the two branches of the common iliac vein however the internal iliac vein and it’s tributaries (including the pudendal vein) are much more important in draining the pelvic structures.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 186
Correct
-
A 69 Year old lady presented to the emergency department following a massive myocardial infarction. She was found to be in hypotensive shock with focal neurological signs. Unfortunately the patient demised. What would be the expected findings on the brain biopsy?
Your Answer: Liquefactive necrosis
Explanation:Liquefactive necrosis is often associated with bacterial or fungal infections. However, hypoxic death of cells within the central nervous system can also result in liquefactive necrosis. The focal area is soft with a liquefied centre containing necrotic debris and dead white cells. This may later be enclosed by a cystic wall
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This question is part of the following fields:
- Cell Injury & Wound Healing; Neurology
- Pathology
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Question 187
Incorrect
-
A 42 year old man with an abdominal aortic aneurysm (AAA) underwent an abdominal aortic angiography which revealed that his inferior mesenteric artery was occluded. If this patient showed no symptoms, the most likely reason is that the area the inferior mesenteric artery supplies, must be supplied by collateral blood flow from which arteries?
Your Answer: Right and middle colic
Correct Answer: Left and middle colic
Explanation:The arterial branches that form an anastomosis between the superior mesenteric artery and the inferior mesenteric artery are the left colic artery and the middle colic artery. The middle colic artery is the most distal branch of the superior mesenteric artery while the left colic forms the most proximal branch of the inferior mesenteric artery. These two arteries will give collateral blood flow in the case that the inferior mesenteric artery gets occluded. The superior mesenteric artery gives off the following branches; ileocolic, appendicular, ileal artery, right colic and middle colic arteries. The left colic, sigmoid and superior rectal arteries are branches of the inferior mesenteric artery. The marginal artery branches off directly from the abdominal aorta.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 188
Correct
-
A biopsy taken from the respiratory passage of a 37 year old male, chronic smoker will mostly likely show which cellular adaptation?
Your Answer: Stratified squamous metaplasia
Explanation:Metaplasia is a change in the cell type caused in part due to an extrinsic stress on the organ. It involves a change in the surface epithelium from one cell type to the another, most commonly squamous to columnar. This is a reversible process, and removal of the stress should theoretically reverse the surface epithelium back to normal morphology. Respiratory tract metaplasia is a classic example, in which the normal pseudostratified columnar epithelium is replaced by stratified squamous epithelium to better cope with the stress. Under continuous stress metaplasia can progress to dysplasia which is a disordered growth of cells eventually leading to the development of carcinoma.
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This question is part of the following fields:
- Cell Injury & Wound Healing; Respiratory
- Pathology
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Question 189
Correct
-
A 50-year-old gentleman was recently diagnosed with hypertension, with no other abnormalities on physical examination. Further investigations revealed the following :
Na+ 144 mmol/l
K+ 3.0 mmol/l
Cl- 107 mmol/l
Bicarbonate 25 mmol/l.
Blood glucose 5.8 mmol/l.
What is the likely diagnosis?Your Answer: Conn syndrome
Explanation:Overproduction of aldosterone (a mineralocorticoid) by the adrenal glands is known as Conn’s syndrome. It can be either due to an aldosterone-secreting adrenal adenoma (50-60% cases) or adrenal gland hyperplasia (40-50% cases). Excess aldosterone leads to sodium and water retention, along with potassium excretion. This leads to arterial (non-essential) hypertension. Conn’s syndrome is the commonest cause of primary hyperaldosteronism. Other symptoms include muscle cramps, headache (due to hypokalaemia) and metabolic alkalosis, which occurs due to increased secretion of H+ ions by the kidney. The raised pH of the blood traps calcium leading to symptoms of hypocalcaemia, which can be mimicked by liquorice ingestion and Liddle syndrome. To diagnose Conn’s syndrome, the ratio of renin and aldosterone is measured. Due to suppression of renin secretion, there is low renin to aldosterone ratio (<0.05). However, anti-hypertensives may affect the test results and should be withdrawn for 6 weeks. Computed tomography can also be done to detect the presence of adrenal adenoma. Cushing’s syndrome does not cause hypokalaemia with normal serum glucose levels. Nelson’s syndrome refers to increased ACTH secretion due to pituitary adenoma. Pheochromocytoma will not lead to hypokalaemia even though hypertension can be seen.
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This question is part of the following fields:
- Endocrine
- Pathology
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Question 190
Incorrect
-
A patient with Paget's disease of the bone is predisposed to developing which type of cancer?
Your Answer: Giant-cell tumour
Correct Answer: Osteosarcoma
Explanation:Paget’s disease of bone (PDB) is a focal disorder of bone. It is presumed benign in nature and mediated by abnormal osteoclast function. However osteosarcomas may occur in <1% of patients with Paget's disease of the bone. Osteosarcomas are osteogenic in origin, and consistently arise in sites of pagetic bone. This is not to be confused with Paget's disease of the breast.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 191
Correct
-
In a hypertensive patient with secondary hyperaldosteronism, aldosterone is released mainly in response to:
Your Answer: Angiotensin II
Explanation:Secondary hyperaldosteronism in hypertension is either due to primary renin overproduction by the kidneys or renin overproduction secondary to decreased renal blood flow. The main stimulus for aldosterone release are adrenocorticotrophic hormone (ACTH), angiotensin II and high plasma K+ levels. Low plasma Na+ might also stimulate the adrenal cortex. Fluid overload will reduce aldosterone secretion. Atrial natriuretic peptide is secreted under conditions of expanded extracellular volume and will not lead to aldosterone secretion.
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This question is part of the following fields:
- Endocrinology
- Physiology
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Question 192
Correct
-
What is the mostly likely cause of prolonged activated partial thromboplastin time (aPPT) ?
Your Answer: Heparin therapy
Explanation:The partial thromboplastin time (PTT) or activated partial thromboplastin time (aPTT) is an indicator for measuring the efficacy of both the intrinsic and common coagulation pathway. Prolonged aPTT may indicate: use of heparin, antiphospholipid antibody and coagulation factor deficiency (e.g., haemophilia). Deficiencies of factors VIII, IX, XI and XII and rarely von Willebrand factor (if causing a low factor VIII level) may lead to a prolonged aPTT correcting on mixing studies.
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This question is part of the following fields:
- General
- Physiology
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Question 193
Correct
-
Which of the following will show decreased hearing when tested by air conduction but normal hearing when tested by bone conduction?
Your Answer: Fibrosis causing fixation of the ossicles
Explanation:As the cochlea is embedded into bone, the vibrations from the bone are transmitted directly to the fluid in the cochlea. Hence, any damage to the ossicles or tympanic membrane will not show an abnormal result on bone conduction test.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 194
Correct
-
In a young, sexually active male, what is the most common cause of non-gonococcal urethritis?
Your Answer: Chlamydia
Explanation:Non-gonococcal urethritis is most commonly caused by Chlamydia trachomatis (50% cases). Less common organisms include Mycoplasma genitalium, Urea urealyticum and Trichomonas vaginalis. Chlamydia is also the commonest cause of non-gonococcal cervicitis in women and proctitis in both sexes.
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This question is part of the following fields:
- Pathology
- Renal
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Question 195
Correct
-
A 72 year old man suffered a MI. What is the approximate time needed by the scar tissue of the MI to recover and attain full strength?
Your Answer: Several months
Explanation:A week following a MI attack, a little collagen starts to form and deposit. By the end of the 2nd week, neovascularisation of the scar occurs, with some collagen being laid down in a haphazard fashion. By this time the scar attains some strength. During the next 6 months, collagen is constantly being laid down and is rearranged in order to shrink the scar. Most of the blood vessels by this time have regenerated, decreasing vascularity of the scar reaching full maturity.
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This question is part of the following fields:
- Cell Injury & Wound Healing; Cardiovascular
- Pathology
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Question 196
Correct
-
A 26-year-old female patient had the following blood report: RBC count = 4. 0 × 106/μl, haematocrit = 27% and haemoglobin = 11 g/dl, mean corpuscular volume (MCV) = 80–100 fl, mean corpuscular haemoglobin concentration (MCHC) = 31–37 g/dl. Which of the following is correct regarding this patient’s erythrocytes:
Your Answer: Normal MCV
Explanation:MCV is the mean corpuscular volume and it is calculated from the haematocrit and the RBC count. It is normally 90 fl. Mean corpuscular haemoglobin concentration (MCHC) [g/dl] = haemoglobin [g/dl]/haematocrit = 11/0.27 = 41 g/dl and is higher than normal range (32 to 36 g/dL).
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This question is part of the following fields:
- General
- Physiology
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Question 197
Correct
-
During a laparoscopic inguinal hernia repair, the surgeon finds an artery in the extraperitoneal connective tissue (preperitoneal fat) that courses vertically and just medial to the bowel as the bowel passes through the abdominal wall. Which artery is this?
Your Answer: Inferior epigastric
Explanation:The inferior epigastric artery comes from the external iliac artery just above the inguinal ligament to curve forward in the subperitoneal tissue and then ascend obliquely along the medial margin of the deep inguinal ring. It continues to ascend between the rectus abdominis and the posterior lamella of its sheath after piercing the fascia transversalis and passing anterior to the linea semicircularis. Finally it gives off numerous branches that anastomose above the umbilicus with the superior epigastric branch of the internal mammary artery and with the lower intercostal arteries. As this artery ascends obliquely upwards from its origin it lies along the lower medial margins of the deep inguinal ring and posterior to the start of the spermatic cord. It is found in the preperitoneal fat of the abdomen lying just superficial to the peritoneum and forms the lateral umbilical fold. Hernias that pass lateral to this are indirect and medial to this, direct hernias.
The deep circumflex artery travels along the iliac crest on the inner surface of the abdominal wall. It is very lateral to the abdominal wall and hernias would pass medial to it.
The superficial circumflex iliac, superficial epigastric, superficial external pudendal arteries are all superficial arteries found in the superficial fascia.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 198
Correct
-
The inferior palpebral nerve ascends behind the orbicularis oculi. What is the terminal branch of the inferior palpebral nerve?
Your Answer: Infraorbital nerve
Explanation:The inferior palpebral nerve is a branch of the maxillary nerve. It supplies the skin and conjunctiva of the lower eyelid.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 199
Correct
-
The gluteus medius muscle:
Your Answer: Is supplied by the superior gluteal nerve
Explanation:The gluteus medius is situated on the outer surface of the pelvis. It arises from the outer surface of the ilium between the iliac crest and posterior gluteal line above and the anterior gluteal line below. The gluteus medius is supplied by the fourth and fifth lumbar and first sacral nerves through the superior gluteal nerve
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 200
Incorrect
-
Which one of the following groups of lymph nodes is most likely to be inflamed due to paronychia involving the big toe?
Your Answer: Lateral group of superficial inguinal lymph nodes
Correct Answer: Vertical group of superficial inguinal lymph nodes
Explanation:Paronychia affecting the big toe will result in inflammation of the superficial inguinal lymph nodes as it drains lymph from the big toe.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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SESSION STATS - PERFORMANCE PER SPECIALTY
