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Question 1
Correct
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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: 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 2
Incorrect
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The Carpal tunnel does NOT contain:
Your Answer: Flexor digitorum superficialis
Correct Answer: Flexor carpi ulnaris
Explanation:The contents of the carpal tunnel include:
– Median nerve
– Flexor digitorum supervicialis
– Flexor digitorum profundus
– Flexor policis longus
– Flexor carpi radialis
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 3
Correct
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In the kidney, the macula densa is an area of closely packed specialized cells lining the wall of the:
Your Answer: Distal convoluted tubule
Explanation:In the kidney, the macula densa is an area of closely packed specialised cells lining the region of the distal convoluted tubule (DCT) lying next to the glomerular vascular pole. The cells of the macula densa are sensitive to the ionic content and water volume of the fluid in the DCT, producing signals that promote renin secretion by other cells of the juxtaglomerular apparatus.
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This question is part of the following fields:
- Physiology
- Renal
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Question 4
Correct
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Inside the palatoglossal arch is a muscle. Which nerve innervates this muscle?
Your Answer: X
Explanation:The palatoglossal arch contains the palatoglossal muscle which is innervated by the vagus nerve which is the tenth cranial nerve. So the correct answer is X
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 5
Correct
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Which best describes the suprascapular nerve?
Your Answer: It contains nerve fibres from C5 and C6 spinal cord segments
Explanation:The suprascapular nerve arises from the cervical spinal nerves 5 and 6 after coming together to form common trunk. This nerve supplies the supraspinatus and infraspinatus muscles giving off branches to the shoulder joint.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 6
Correct
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If a 70-year-old man with known atrial fibrillation dies suddenly, which of these is the most likely cause of death?
Your Answer: Thromboembolism
Explanation:In atrial fibrillation, the abnormal atrial contraction can cause blood to stagnate in the left atrium and form a thrombus, which may then embolize. The patient’s history of AF suggest an embolic disease, which lead to his death.
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This question is part of the following fields:
- Cardiovascular
- Pathology
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Question 7
Incorrect
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Which of the following proteins prevents red blood cells (RBCs) from bursting when they pass through capillaries?
Your Answer: Albumin
Correct Answer: Spectrin
Explanation:Spectrin is a structural protein found in the cytoskeleton that lines the intercellular side of the membrane of cells which include RBCs. They maintain the integrity and structure of the cell. It is arranged into a hexagonal arrangement formed from tetramers of spectrin and associated with short actin filaments that form junctions allowing the RBC to distort its shape.
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This question is part of the following fields:
- General
- Physiology
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Question 8
Correct
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Out of the given options, which of the following is the most likely diagnosis in a 25-year old gentleman presenting with a testicular germ cell tumour?
Your Answer: Embryonal carcinoma
Explanation:Embryonal carcinoma is a non-seminomatous germ cell tumour of the testis, accounting for 25% testicular tumours. Other germ cell tumours include seminoma, teratoma and choriocarcinoma. Embryonal carcinomas are known to occur in men aged 25-35 years, and occasionally in teens. They are rarely seen in ovaries of females. It can spread to the vas deferens and also to the aortic lymph nodes. Embryonal carcinomas are known to have elements of fetal origin such as cartilage. Usually, the main tumour is about 2.5cm long, with an extension of 8-9cm along the testicular cord. Contiguous spread to the testicle is seen in less than 1% cases.
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This question is part of the following fields:
- Pathology
- Urology
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Question 9
Correct
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From which branchial (pharyngeal) pouch does the inferior parathyroid gland arise?
Your Answer: 3rd
Explanation:The following structures arise from each branchial pouch:
1st pouch – eustachian tube, middle ear, mastoid, and inner layer of the tympanic membrane
2nd pouch – middle ear, palatine tonsils
3rd pouch – inferior parathyroid glands, thymus
4th pouch – superior parathyroid glands, ultimobranchial body which forms the parafollicular C-cells of the thyroid gland, musculature and cartilage of larynx (along with the sixth pharyngeal pouch)
5th pouch – rudimentary structure
6th pouch – along with the fourth pouch, contributes to the formation of the musculature and cartilage of the larynx.
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This question is part of the following fields:
- Anatomy
- Endocrine; Embryology
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Question 10
Correct
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A patient gives a history of dull discomfort in her abdomen associated with pain that she points to be on her right shoulder and right scapula. The following organs are most likely to be source of her pain:
Your Answer: Liver, duodenum and gallbladder
Explanation:Referred pain is felt at a point away from the source of the pain or the unpleasant sensation. It arises when a nerve is damaged or compressed at a point but the pain is felt at another site that is the territory of that nerve. Common abdominal causes of referred pain to the shoulder and the shoulder blade are the liver, duodenum and gall bladder.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 11
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 12
Incorrect
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The stomach is an organ that is divided into several important anatomical parts. These parts of the stomach have varied arterial blood supply that ensure that the whole organ receive oxygenated blood. Which of the following arteries if ligated, will not render any portion of the stomach ischaemic?
Your Answer: Short gastric
Correct Answer: Superior mesenteric
Explanation:The blood supply to the stomach is through the following arteries:
– The superior mesenteric artery supplies blood to the lower part of the duodenum, pancreas and two-thirds of the transverse colon. Thus ligation of the superior mesenteric artery would not affect the stomach.
– The right and the left gastroepiploic arteries supply the greater curvature of the stomach – along its edges.
– The short gastric artery supplies blood to the upper portion of the of the greater curvature and the fundus of the stomach.
– The gastroduodenal artery supplies blood to the distal part of the stomach (the pyloric sphincter) and the proximal end of the duodenum.
– The left gastroepiploic and the short gastric are branches of the splenic artery and therefore ligation of the splenic artery would directly affect the stomach.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 13
Correct
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A patient with Paget's disease of the bone is predisposed to developing which type of cancer?
Your 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 14
Incorrect
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A 45-year-old man complains of shortness of breath, cough and chest pain. Chest X ray revealed a perihilar mass with bronchiectasis in the left mid-lung. Which of the following is most probably associated with these findings?
Your Answer: Pulmonary hamartoma
Correct Answer: Bronchial carcinoid
Explanation:Bronchial carcinoids are neuroendocrine tumours that arise from Kulchitsky’s cells of the bronchial epithelium. Kulchitsky’s cells belong to the diffuse endocrine system. Patients affected by this tumour may be asymptomatic or may present with symptoms of airway obstruction, like dyspnoea, wheezing, and cough. Other common findings are recurrent pneumonia, haemoptysis, chest pain and paraneoplastic syndromes. Chest radiographs are abnormal in the majority of cases. Peripheral carcinoids usually present as a solitary pulmonary nodule. For central lesions common findings include hilar or perihilar masses with or without atelectasis, bronchiectasis, or consolidation. Bronchial carcinoids most commonly arise in the large bronchi causing obstruction.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 15
Incorrect
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The most important difference between interstitial fluid and plasma is the:
Your Answer: Concentration of sodium
Correct Answer: Protein concentration
Explanation:Interstitial fluid (or tissue fluid or intercellular fluid) is a solution that surrounds the cells of multicellular animals. It is the main component of the extracellular fluid, which also includes plasma, lymph and transcellular fluid. Plasma, the major component in blood, communicates freely with interstitial fluid through pores and intercellular clefts in capillary endothelium. Interstitial fluid consists of a water solvent containing amino acids, sugars, fatty acids, coenzymes, hormones, neurotransmitters, salts, as well as waste products from the cells. Red blood cells, platelets and plasma proteins cannot pass through the walls of the capillaries. The resulting mixture that does pass through is essentially blood plasma without the plasma proteins. Tissue fluid also contains certain types of white blood cells. Once the extracellular fluid collects into small vessels it is considered to be lymph, and the vessels that carry it back to the blood are called the lymphatic vessels. The lymphatic system returns protein and excess interstitial fluid to the circulation.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 16
Correct
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A man had noticed weakness in his left arm causing flexion of the elbow and supination of the forearm. Which nerve in this case was injured?
Your Answer: Musculocutaneous
Explanation:The musculocutaneous nerve supplies the biceps brachii and the brachialis muscles. The first one flexes the elbow and the shoulder. It is also involved in supination. The brachialis muscle flexes the forearm. The injury to the musculocutaneous nerve results in paralysis of these muscles.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 17
Correct
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A 65-year old patient with altered bowl movement experienced the worsening of shortness of breath and exertional chest pains over the course of 8 weeks. Examination shows pallor and jugular venous distension. Furthermore, a test of the stool for occult blood is positive. Laboratory studies show:
Haemoglobin 7.4 g/dl
Mean corpuscular volume 70 fl Leukocyte count 5400/mm3
Platelet count 580 000/mm3 Erythrocyte sedimentation 33 mm/h
A blood smear shows hypochromic, microcytic RBCs with moderate poikilocytosis. Which of the following is the most likely diagnosis?Your Answer: Iron deficiency anaemia
Explanation:Iron deficiency anaemia is the most common type of anaemia. It can occur due to deficiency of iron due to decreased intake or due to faulty absorption. An MCV less than 80 will indicated iron deficiency anaemia. On the smear the RBC will be microcytic hypochromic and will also show piokilocytosis. iron profiles tests are important to make a diagnosis. Clinically the patient will be pale and lethargic.
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This question is part of the following fields:
- General
- Physiology
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Question 18
Correct
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The extent of cancer growth can be described through staging. What is taken into consideration when staging a cancer?
Your Answer: Local invasion
Explanation:Cancer stage is based on four characteristics: the size of cancer, whether the cancer is invasive or non-invasive, whether the cancer has spread to the lymph nodes, and whether the cancer has spread to other parts of the body, in this case beyond the breast. Staging is important as it is often a good predictor of outcomes and treatment is adjusted accordingly.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 19
Correct
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Which of the following conditions can present with multiple abscesses that may discharge sulphur granules?
Your Answer: Actinomycosis
Explanation:Actinomycosis is primarily caused by any of the several members of the bacterial genus Actinomyces. These bacteria are generally anaerobes. And can cause multiple abscesses that may discharge sulphur granules.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 20
Correct
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The prostatic plexus of nerves contains nerve fibres that innervate penile tissue allowing for erection. From which of the following nerves do these fibres originate?
Your Answer: Pelvic splanchnics
Explanation:Pelvic splanchnic nerves are examples of the parasympathetic nerves that innervate the smooth muscle and glands of the pelvic viscera. They are also the nerves contributing fibres to the prostatic plexus which innervate penile erectile tissue.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 21
Correct
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A 20-year old college student was diagnosed with meningitis that had developed due to an acute cavernous sinus thrombosis from an ear infection. Which of the following superficial venous routes is the usual path that an infected blood clot takes to reach the cavernous sinus?
Your Answer: Facial vein
Explanation:The facial vein is the usual communication between the cavernous sinus and the pterygoid sinus. It is through this vein that an infected clot can travel to the cavernous sinus and cause infection. The pterygoid plexus is a venous plexus that is situated between the temporalis muscle and lateral pterygoid muscle, and partly between the two pterygoid muscles. The pterygoid plexus is connected to the facial vein by the deep facial vein. This connection is what makes this area where this sinus and the facial vein are located a danger zone. The danger zone or triangle of the face is the area from the corners of the mouth to the nose bridge. The sinus connection in this area makes it possible for infection to reach the cavernous sinus and at times cause meningitis.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 22
Correct
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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 23
Correct
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Pain in the right upper quadrant of the abdomen on ingestion of a fatty meal is seen in a condition which involves which of the following substances?
Your Answer: Cholecystokinin
Explanation:The clinical scenario described here favours the presence of gallstones. During food ingestion, vagal discharges stimulate gallbladder contraction. Moreover, presence of fat and amino acids in the intestinal lumen stimulates the release of cholecystokinin (CCK) in the duodenum. This causes sustained gallbladder contraction and relaxation of the sphincter of Oddi. If gallstones are present, there will be inflammation in the gallbladder and CCK will aggravate it due to contractions.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 24
Correct
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An old man was diagnosed with squamous cell carcinoma with axillary lymph node metastasis. The doctor said he will excise the tumour and remove all axillary lymph nodes medial to the edge of the pectoralis minor muscle. One of the following axillary lymph nodes won't be removed by this procedure. Which is it?
Your Answer: Apical
Explanation:The apical lymph node group won’t be removed which include 20 to 30 lymph nodes. They are grouped according to location. The lateral group, the anterior to pectoral group, the posterior or subscapular group, the central group, and the medial or apical group. The lateral, pectoral, and subscapular groups are found lateral to the pectoralis minor muscle. The central group is situated directly under that muscle. Thus, if all lymph nodes lateral to the medial edge of the pectoralis minor muscle are removed, all the above four groups will be removed. The apical group won’t be removed which is situated medial to the medial edge of the pectoralis minor muscle.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 25
Incorrect
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The thyroid gland is a large ductless gland located in which part of the neck?
Your Answer: Posterior triangle
Correct Answer: Visceral space
Explanation:The thyroid gland is an endocrine gland in the neck, consisting of two lobes connected by an isthmus. It is situated at the front and sides of the neck in the visceral space.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 26
Correct
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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 27
Incorrect
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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: Musculocutaneous
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 28
Correct
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After a prolonged coronary artery bypass surgery, a 60-year old gentleman was transfused 3 units of fresh-frozen plasma and 2 units of packed red cells. Two days later, the nurse noticed that he was tachypnoeic and chest X-ray showed signs consistent with adult respiratory distress syndrome. Which of the following variables will be low in this patient?
Your Answer: Compliance of the lung
Explanation:Acute or adult respiratory distress syndrome (ARDS) is a reaction to several forms of lung injuries and is commonly associated with sepsis and SIRS (systemic inflammatory response syndrome), severe traumatic injury, severe head injury, narcotics overdose, drowning, pulmonary contusion, and multiple blood transfusions. There is an increase in risk due to pre-existing liver disease or coagulation abnormalities. It results due to indirect toxic effects of neutrophil-derived inflammatory mediators in the lungs. ARDS is defined by the 1994 American–European Consensus Committee as the acute onset of bilateral infiltrates on chest X-ray, a partial pressure of arterial oxygen (pa(O2)) to fraction of inspired oxygen Fi(O2) ratio of less than 200 mmHg and a pulmonary artery occlusion pressure of less than 18 or the absence of clinical evidence of left arterial hypertension. ARDS is basically pulmonary oedema in the absence of volume overload or poor left ventricular function. This is different from acute lung injury, which shows a pa(O2)/Fi(O2) ratio of less than 300 mmHg. Pathogenesis of ARDS starts from damage to alveolar epithelium and vascular endothelium, causing increased permeability. Damage to surfactant-producing type II cells disrupts the production and function of pulmonary surfactant, causing micro atelectasis and poor gas exchange. There is a decrease in lung compliance and increase in work of breathing. Eventually, there is resorption of alveolar oedema, regeneration of epithelial cells, proliferation and differentiation of type II alveolar cells and alveolar remodelling. Some show resolution and some progress to fibrosing alveolitis, which involves the deposition of collagen in alveolar, vascular and interstitial spaces.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 29
Correct
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A 65-year-old man complains of headaches, weakness, cramps, and confusion; blood tests reveal he has severe hyponatremia. The most likely cause is:
Your Answer: Severe diarrhoea or vomiting
Explanation:Hyponatraemia occurs when the sodium level in the plasma falls below 135 mmol/l. Hyponatraemia is an abnormality that can occur in isolation or, more commonly as a complication of other medical illnesses. Severe hyponatraemia may cause osmotic shift of water from the plasma into the brain cells. Typical symptoms include nausea, vomiting, headache and malaise. As the hyponatraemia worsens, confusion, diminished reflexes, convulsions, stupor or coma may occur. The cause of hyponatremia is typically classified by a person’s fluid status into low volume, normal volume, and high volume. Low volume hyponatremia can occur from diarrhoea, vomiting, diuretics, and sweating.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 30
Correct
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In the glomerulus of the kidney, the mesangium is a structure associated with the capillaries. It has extraglomerular mesangial cells that:
Your Answer: Form the juxtaglomerular apparatus in combination with the macula densa and juxtaglomerular cells
Explanation:The mesangium is an inner layer of the glomerulus, within the basement membrane surrounding the glomerular capillaries. The mesangial cells are phagocytic and secrete the amorphous basement membrane-like material known as the mesangial matrix. They are typically separated from the lumen of the capillaries by endothelial cells. The other type of cells in the mesangium are the extraglomerular mesangial cells which form the juxtaglomerular apparatus in combination with two other types of cells: the macula densa of the distal convoluted tubule and juxtaglomerular cells of the afferent arteriole. This apparatus controls blood pressure through the renin–angiotensin–aldosterone system.
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This question is part of the following fields:
- Physiology
- Renal
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Question 31
Incorrect
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The superior ulnar collateral artery is a direct branch of this artery:
Your Answer: Ulnar
Correct Answer: Brachial
Explanation:The brachial artery gives rise to a small branch at the middle of the arm, which is the superior collateral artery. It descends accompanied by the ulnar nerve and anastomoses with the posterior ulnar recurrent and inferior ulnar collateral.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 32
Correct
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Below which level of the spinal cord will the inferior gluteal nerve be unaffected?
Your Answer: S3
Explanation:The inferior gluteal nerve arises from the dorsal divisions of the fifth lumbar and first and second sacral nerves. According to this fact any lesion at or below the S3 will not affect the inferior gluteal nerve.
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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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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 34
Incorrect
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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: Decreased human chorionic gonadotrophin
Correct 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 35
Incorrect
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In a neurological exam on a robbery with violence victim, it was discovered that the victim had lost sense of touch to the skin over her cheek and chin (maxilla and mandible region). Where are the cell bodies of the nerve that is responsible for touch sensations of this region located?
Your Answer: Cranial nerve VII ganglion
Correct Answer: Cranial nerve V ganglion
Explanation:The skin over the cheek and the maxilla are innervated by the trigeminal nerve (CN V). The trigeminal nerve has three major branches and it is the largest cranial nerve. The three branches of the trigeminal nerve are; the ophthalmic nerve, the maxillary nerve and the mandibular nerve. The trigeminal nerves ganglion is a sensory nerve ganglion know as the trigeminal ganglion (also referred to as the Gasser’s ganglion or the semilunar ganglion). It is contained in the dura matter in a cavity known as the Meckel’s cave, which covers the trigeminal impression near the apex of the petrous part of the temporal bone.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 36
Correct
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A 23-year-old woman decides to donate a kidney through a kidney chain. Which of the following indices would be expected to be decreased in the donor after full recovery from the operation?
Your Answer: Creatinine clearance
Explanation:Since medication to prevent rejection is so effective, donors do not need to be similar to their recipient. Most donated kidneys come from deceased donors; however, the utilisation of living donors is on the rise. Most problems encountered with live donation are associated with the donor. Firstly, there are the potentially harmful investigative procedures carried out in the assessment phase, the most hazardous being renal angiography, where there is cannulation of the artery and injection of a radio-opaque dye to determine the blood supply to the kidney. Secondly, there are the short-term risks of nephrectomy surgery. According to the literature, there is a mortality rate of between 1 in 1600 and 1 in 3000, but this is no more than is associated with any anaesthetic. In the initial postoperative period creatinine clearance may be decreased but this recovers fully over a few weeks to months. Long-term complications include prolonged wound pain.
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This question is part of the following fields:
- Physiology
- Renal
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Question 37
Correct
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The periphery of a haematoma is infiltrated by fibroblasts, collagen and new vasculature. This process is best described as?
Your Answer: Organisation of the haematoma
Explanation:Formation of granulation tissue at the periphery of the hematoma is a normal process leading to resolution. This granulation tissue is composed of new capillaries, fibroblasts and collagen. Lysis of a blood clot can occur, but the actual process of this response is known as organization, wherein the scar tissue will become part of the vessels. This is followed by recanalization and embolization which can lead to eventual complications. Proliferation of a clot will occur due to an imbalance in the clotting and lysing systems. Thrombosis has nothing to do with the process described above.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 38
Incorrect
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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 39
Incorrect
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Different portions of the renal tubule have varying degrees of water permeability. Which of the following renal sites is characterised by low water permeability under normal circumstances?
Your Answer: Proximal tubule
Correct Answer: Thick ascending limb of the loop of Henlé
Explanation:Within the nephron of the kidney, the ascending limb of the loop of Henle is a segment of the loop of Henle downstream of the descending limb, after the sharp bend of the loop. Both the thin and the thick ascending limbs of the loop of Henlé have very low permeability to water. Since there are no regulatory mechanisms to alter its permeability, it remains poorly permeable to water under all circumstances. Sodium and chloride are transported out of the luminal fluid into the surrounding interstitial spaces, where they are reabsorbed. Water must remain behind because it is not reabsorbed, so the solute concentration becomes less and less (the luminal fluid becomes more dilute). This is one of the principal mechanisms (along with diminution of ADH secretion) for the production of a dilute, hypo-osmotic urine (water diuresis).
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This question is part of the following fields:
- Physiology
- Renal
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Question 40
Incorrect
-
The mandibular nerve, which is the largest of the 3 divisions of the trigeminal nerve, exits the cranial cavity through which foramen?
Your Answer: Foramen magnum
Correct Answer: Foramen ovale
Explanation:At the base of the skull the foramen ovale is one of the larger of the several holes that transmit nerves through the skull. The following structures pass through foramen ovale: mandibular nerve, motor root of the trigeminal nerve, accessory meningeal artery, lesser petrosal nerve, a branch of the glossopharyngeal nerve, emissary vein connecting the cavernous sinus with the pterygoid plexus of veins and occasionally the anterior trunk of the middle meningeal vein.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 41
Incorrect
-
What is the correct order of structures a needle must pass before it enters the pleural cavity?
Your Answer: External intercostals – innermost intercostals – internal intercostals – parietal pleura
Correct Answer: External intercostals – internal intercostals – innermost intercostals – parietal pleura
Explanation:The correct order of structures from superficial to deep are: the skin and subcutaneous tissue, the external intercostals followed by internal intercostals, innermost intercostals and finally parietal pleura.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 42
Correct
-
Which of the following mediators of inflammation requires arachidonic acid for synthesis?
Your Answer: Prostaglandins
Explanation:Arachidonic acid is normally present in the phospholipids that make up the cell membrane and is cleaved by phospholipase A2 from the phospholipid. Arachidonic acid is a precursor for the production of eicosanoids which include: 1) prostaglandins, prostacyclins and thromboxane, 2) leukotrienes and 3) anandamides. The production of these products along with their action on the body is called the arachidonic acid cascade.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 43
Incorrect
-
Lack of findings in the bladder but presence of atypical epithelial cells in urinalysis is most often associated with which of the following conditions?
Your Answer: Squamous cell carcinoma of penis
Correct Answer: Transitional cell carcinoma of renal pelvis
Explanation:The presence of atypical cells in urinalysis without findings in the bladder suggests a lesion located higher up, most probably in ureters or renal pelvis. Transitional cell cancer of the renal pelvis is a disease in which malignant cells form in the renal pelvis and is characterised by the presence of abnormal cells in urine cytology.
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This question is part of the following fields:
- Pathology
- Renal
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Question 44
Correct
-
When at rest, which of the following will be higher in a marathon runner compared to an untrained individual?
Your Answer: Cardiac stroke volume
Explanation:Cardiac muscle hypertrophy is seen in trained athletes as compared to the normal population. This hypertrophy results in higher stroke volume at rest and increased cardiac reserve (maximum cardiac output during exercise). However, the cardiac output at rest is almost the same in both trained and untrained people. This is because in trained athletes, the heart rate is slower, even up to 40-50 beats/min. There is minimal affect of athletic training on oxygen consumption and respiratory rate.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 45
Correct
-
A 45 year old lady has been diagnosed with Friedreich's ataxia that has affected her medial group of nuclei in the anterior horn of the spinal cord. Which of the following structures will have their muscles affected?
Your Answer: Axial muscles
Explanation:The cells in the anterior horn can be arranged in the following three main groups: medial, lateral and central. The medial group of nuclei in the anterior horn of the spinal cord are located along the entire length of the spinal cord and are responsible for the innervation of the axial muscles of the body ( muscles of the head and neck region). Thus this disease will most likely affect the functioning of the muscles of the head and neck.
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This question is part of the following fields:
- Anatomy
- Neurology
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Question 46
Incorrect
-
Which of the following is the most common germ cell tumour of the testis affecting an adult male?
Your Answer: Teratoma
Correct Answer: Seminoma
Explanation:Germ cell tumours represent 90% of primary tumours arising in the testis. They are broadly divided into seminomas and non-seminomas. Seminomas are the most common testicular germ cell tumour seen in 40% cases. The other non-seminomatous histological subtypes include embryonal (25%), teratocarcinoma (25%), teratoma (5%) and pure choriocarcinoma (1%).
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This question is part of the following fields:
- Pathology
- Urology
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Question 47
Incorrect
-
Which of the following statements regarding the femoral artery is CORRECT?
Your Answer: It pierces the adductor longus muscle
Correct 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 48
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
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Question 49
Incorrect
-
A 59-year old gentleman admitted for elective cholecystectomy was found to have a haemoglobin 12.5 g/dl, haematocrit 37%, mean corpuscular volume 90 fl, platelet count 185 × 109/l, and white blood cell count 32 × 109/l; along with multiple, small mature lymphocytes on peripheral smear. The likely diagnosis is:
Your Answer: Acute lymphocytic leukaemia
Correct Answer: Chronic lymphocytic leukaemia
Explanation:CLL or chronic lymphocytic leukaemia is the most common leukaemia seen in the Western world. Twice more common in men than women, the incidence of CLL increases with age. About 75% cases are seen in patients aged more than 60 years. The blood, marrow, spleen and lymph nodes all undergo infiltration, eventually leading to haematopoiesis (anaemia, neutropenia, thrombocytopenia), hepatomegaly, splenomegaly and decreased production of immunoglobulin. In 98% cases, CD+5 B cells undergo malignant transformation.
Often diagnosed on blood tests while being evaluated for lymphadenopathy, CLL causes symptoms like fatigue, anorexia, weight loss, pallor, dyspnoea on exertion, abdominal fullness or distension. Findings include multiple lymphadenopathy with minimal-to- moderate hepatomegaly and splenomegaly. Increased susceptibility to infections is seen. Herpes Zoster is common. Diffuse or maculopapular skin infiltration can also be seen in T-cell CLL.
Diagnosis is by examination of peripheral blood smear and marrow: hallmark being a sustained, absolute leucocytosis (>5 ×109/l) and increased lymphocytes in the marrow (>30%). Other findings can include hypogammaglobulinemia (<15% of cases) and, rarely, raised lactate dehydrogenase (LDH). Only 10% cases demonstrate moderate anaemia and/or thrombocytopenia.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 50
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 51
Correct
-
The majority of gallstones are mainly composed of:
Your Answer: Cholesterol
Explanation:Bile salts are formed out of cholesterol in the liver cells. Occasionally, precipitation of cholesterol occurs resulting into cholesterol stones developing in the gall bladder.
These cholesterol gallstones are the most common type and account for 80% of all gallstones. Another type, accounting for 20% gallstones is pigment stones which are composed of bilirubin and calcium salts. Occasionally, stones of mixed origin are also seen.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 52
Incorrect
-
Which of these HLA alleles is most likely to be present in ankylosing spondylitis?
Your Answer: HLA-W6
Correct Answer: HLA-B27
Explanation:Ankylosing spondylitis usually appears between the ages of 20-40 years old and is more frequent in men. It is strongly associated with HLA-B27, along with other spondyloarthropathies, which can be remembered through the mnemonic PAIR (Psoriasis, Ankylosing spondylitis, Inflammatory bowel disease, and Reactive arthritis).
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 53
Incorrect
-
The pleural cavity is the space between the two pulmonary pleurae which cover the lungs. What is the normal amount of pleural fluid?
Your Answer: 250 ml
Correct Answer: 10 ml
Explanation:Pleural fluid is a serous fluid produced by the serous membrane covering normal pleurae. Most fluid is produced by the parietal circulation (intercostal arteries) via bulk flow and reabsorbed by the lymphatic system. The total volume of fluid present in the intrapleural space is estimated to be only 2–10 ml. A small amount of protein is present in intrapleural fluid. Normally, the rate of reabsorption increases as a physiological response to accumulating fluid.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 54
Correct
-
A 66 year old male, was involved in a MVA. He sustained third degree burns to his abdomen and open bleeding wound to his left leg. The patient complains of dizziness. He is a known hypertensive but during examination was found to be hypotensive. His heart rate is 120/min, with regular rhythm. What is the possible cause of his hypotension?
Your Answer: Hypovolaemia
Explanation:Hypovolemia can be recognized by tachycardia, diminished blood pressure, and the absence of perfusion as assessed by skin signs (skin turning pale) and/or capillary refill time. The patient may feel dizzy, faint, nauseated, or very thirsty. Common causes of hypovolemia are loss of blood, loss of plasma which occurs in severe burns and lesions discharging fluid, loss of body sodium and consequent intravascular water which may occur in cases of diarrhoea and vomiting. In this case the cause of patients hypotension is due to hypovolemia from both loss of plasma and blood.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 55
Incorrect
-
Regarding the coagulation cascade, Factor VII:
Your Answer: Activates factor X
Correct Answer: Is a serine protease
Explanation:Factor VII (FVII) is a zymogen for a vitamin K-dependent serine protease essential for the initiation of blood coagulation. It is synthesized primarily in the liver and circulates in plasma. Within the liver, hepatocytes are involved in the synthesis of most blood coagulation factors, such as fibrinogen, prothrombin, factor V, VII, IX, X, XI, XII, as well as protein C and S, and antithrombin, whereas liver sinusoidal endothelial cells produce factor VIII and von Willebrand factor.
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This question is part of the following fields:
- General
- Physiology
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Question 56
Correct
-
A patient with this condition has extracellular fluid volume expansion:
Your Answer: Nephrotic syndrome
Explanation:Nephrotic syndrome is a syndrome comprising of signs of nephrosis, including proteinuria, hypoalbuminemia, and oedema. It is a component of glomerulonephritis, in which different degrees of proteinuria occur. Essentially, loss of protein through the kidneys leads to low protein levels in the blood , which causes water to be drawn into soft tissues (oedema). Severe hypoalbuminemia can also cause a variety of secondary problems, such as water in the abdominal cavity (ascites), around the heart or lung (pericardial effusion, pleural effusion), high cholesterol, loss of molecules regulating coagulation (hence increased risk of thrombosis). The most common sign is excess fluid in the body due to the serum hypoalbuminemia. Lower serum oncotic pressure causes fluid to accumulate in the interstitial tissues. Sodium and water retention aggravates the oedema.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 57
Incorrect
-
Which muscles are attached to the tibial tuberosity?
Your Answer: Pectineus
Correct Answer: Vastus intermedius
Explanation:The tuberosity of the tibia is the site of attachment to the ligamentum patella (the tendon of the quadriceps femoris muscle which include four heads: rectus femoris, vastus medialis, intermedius and lateralis).
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 58
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 59
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 60
Correct
-
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 61
Correct
-
A butcher accidentally cut himself on his right index finger. Which of the following substances when in contact with the basement membrane of the injured vasculature will activate the coagulation cascade as well as the kinin system in a first response to this injury?
Your Answer: Hageman factor
Explanation:Hageman factor/factor XII in the intrinsic pathway activates prekallikrein and factor XI. Deficiency will not cause excessive bleeding as other coagulation factors will be utilized but the PTT will be greater than 200 seconds.
Thromboxane promotes platelet aggregation and causes vasoconstriction.
Plasmin, which is cleaved from plasminogen acts as an anticoagulant which breaks down thrombi.
Platelet activating factor promotes platelet aggregation and is also chemotactic to neutrophils.
Histamine acts as a vasodilator.
Platelet inhibiting factor acts an anticoagulant.
Renin is a hormone released from the kidney that causes vasoconstriction and water retention.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 62
Incorrect
-
A 40-year old gentleman, who is a known with ulcerative colitis, complains of recent-onset of itching and fatigue. On examination, his serum alkaline phosphatase level was found to be high. Barium radiography of the biliary tract showed a 'beaded' appearance. What is the likely diagnosis?
Your Answer: Chronic cholelithiasis
Correct Answer: Sclerosing cholangitis
Explanation:Primary sclerosing cholangitis is characterised by patchy inflammation, fibrosis and strictures in intra- and extra-hepatic bile ducts. It is a chronic cholestatic condition with 80% patients having associated inflammatory bowel disease (likely to be ulcerative colitis). Symptoms include pruritus and fatigue. ERCP (endoscopic retrograde cholangiopancreatography) or MRCP (magnetic resonance cholangiopancreatography) are diagnostic. Disease can lead to complete obliteration of ducts, which can result in liver failure. Cholangiocarcinoma is also a recognised complication..
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 63
Correct
-
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 64
Incorrect
-
Which of the following morphological features is most characteristic of hyaline degeneration?
Your Answer: Accumulation of lipofuscin
Correct Answer: Homogeneous, ground-glass, pink-staining appearance of cells
Explanation:The characteristic morphological features of hyaline degeneration is ground-glass, pinking staining cytoplasm with an intact cell membrane. The accumulation of lipids, calcium salts, lipofuscin and an amorphous cytoplasm with an intact cell membrane are all characteristically found in different situations.
Pyknotic nucleus and orphan Annie eye nucleus are not seen in hyaline degeneration.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 65
Incorrect
-
Which of the following morphological characteristic is a salient feature of a pure apoptotic cell?
Your Answer: Plasma membrane breakdown
Correct Answer: Chromatin condensation
Explanation:Apoptosis is the programmed death of cells which occurs as a normal and controlled part of an organism’s growth or development. The changes which occur in this process include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, chromosomal DNA fragmentation, and global mRNA decay. The cell membrane however remains intact and the dead cells are phagocytosed prior to any content leakage and thus inflammatory response.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 66
Correct
-
A 29-year-old pregnant woman suffering from hyperemesis gravidarum is prescribed metoclopramide. What is the mechanism of action of metoclopramide?
Your 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 67
Correct
-
A 14 year-old girl is found to have haemophilia B. What pathological problem does she have?
Your 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 68
Correct
-
A 78-year-old diabetic man undergoes renal function tests. Which of the following substances will be the most accurate for measuring glomerular filtration rate (GFR)?
Your Answer: Inulin
Explanation:Glomerular filtration rate (GFR) is the volume of fluid filtered from the renal glomerular capillaries into the Bowman’s capsule per unit time. Clinically, this is often measured to determine renal function. Inulin was originally used as it is not reabsorbed by the kidney after glomerular filtration, therefore its rate of excretion is directly proportional to the rate of filtration of water and solutes across the glomerular filter. However, in clinical practice, creatinine clearance is used to measure GFR. Creatinine is an endogenous molecule, synthesised in the body, that is freely filtered by the glomerulus (but also secreted by the renal tubules in very small amounts). Creatinine clearance exceeds GFR due to creatinine secretion, and is therefore a close approximation of the GFR.
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This question is part of the following fields:
- Physiology
- Renal
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Question 69
Incorrect
-
What is expected from complete transection of the inferior gluteal nerve when it emerges from the greater sciatic foramen?
Your Answer: Muscles in the posterior compartment of the leg would be paralysed
Correct Answer: Extension of the thigh would be the action most affected
Explanation:As the inferior gluteal nerve emerges from the greater sciatic foramen below the piriformis muscle, it divides into branches and enters the gluteus maximus muscle which extends the femur and bends the thigh in line with the body.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 70
Correct
-
The anatomical course of the phrenic nerve passes over the following muscle in the neck?
Your 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 71
Incorrect
-
The blood-brain barrier is a membrane that separates the circulating blood from the brain extracellular fluid in the central nervous system (CNS). Which of the following statements regarding the blood– brain barrier is CORRECT?
Your Answer: All regions of the brain have a blood-brain barrier
Correct Answer: It breaks down in areas of brain that are infected
Explanation:The blood–brain barrier is a membrane that controls the passage of substances from the blood into the central nervous system. It is a physical barrier between the local blood vessels and most parts of the central nervous system and stops many substances from travelling across it. During meningitis, the blood–brain barrier may be disrupted. This disruption may increase the penetration of various substances (including either toxins or antibiotics) into the brain. A few regions in the brain, including the circumventricular organs, do not have a blood–brain barrier.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 72
Incorrect
-
The renal tubule is the portion of the nephron that contains the fluid that has been filtered by the glomerulus. Which of the following substances is actively secreted into the renal tubules?
Your Answer: Amino acids
Correct Answer: Potassium
Explanation:The renal corpuscle filters out solutes from the blood, delivering water and small solutes to the renal tubule for modification. In normal circumstances more than 90% of the filtered load of K is reabsorbed by the proximal tubules and loops of Henlé and almost all K appearing in the urine has been secreted by the late distal tubules and collecting tubules. So the rate of excretion is usually independent of the rate of filtration, but is closely tied to the rate of secretion and control of K excretion, largely accomplished by control of the secretion rate. Around 65–70% of the filtered potassium is reabsorbed along with water in the proximal tubule and the concentration of potassium in the tubular fluid varies little from that of the plasma.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 73
Incorrect
-
A 60 year old female patient who has suffered an embolic stroke that affected her middle cerebral artery as revealed by a CT scan is likely to exhibit which of the following neurologic conditions?
Your Answer: Ipsilateral hemiplegia
Correct Answer: Contralateral hemiplegia
Explanation:The middle cerebral artery is a major artery that supplies blood to the cerebrum. It continues from the internal carotid artery up into the lateral sulcus. The middle cerebral artery mainly supplies the lateral aspect of the cerebral cortex, anterior aspect of the temporal lobes and the insular cortices.
Functional areas supplied by this vein are as follows:
The motor and pre-motor areas
The somato-sensory
Auditory areas
Motor speech
Sensory speech
Pre-frontal area
Occlusion of the middle cerebral artery results in:
i) A severe contralateral hemiplegia, most marked in the upper extremity and face
ii) A contralateral sensory impairment worse in the upper part of the body.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 74
Incorrect
-
A elderly patient with bulbar palsy is bed ridden. While swallowing he aspirates one of his tablets into his lungs. In which bronchopulmonary segments is it most likely to end up?
Your Answer: Anterior segmental bronchus of the right superior lobe
Correct Answer: Superior segmental bronchus of the right inferior lobe
Explanation:Inhaled objects are more likely to enter the right lung for several reasons. First the right bronchus is shorter, wider and more vertical than the left bronchus. Also, the carina (a ridge-like structure at the point of tracheal bifurcation) is set a little towards the left. The superior segmental bronchus branches posteriorly off the intermediate bronchus or the inferior lobe bronchus and is thus more likely to receive the foreign body that enters the right main bronchus. The lingula is only found on the left lung. The terminal bronchiole is a very small space almost impossible for the tablet to lodge here.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 75
Incorrect
-
A 6 year-old boy is brought to you coughing. He is suspected to have aspirated a Lego piece which he was seen playing with. Where would you expect the piece to be?
Your Answer: Left main bronchus
Correct Answer: Right main bronchus
Explanation:Inhaled objects are more likely to enter the right lung for several reasons. First the right bronchus is shorter, wider and more vertical than the left bronchus. Also, the carina (a ridge-like structure at the point of tracheal bifurcation) is set a little towards the left. The terminal bronchiole is a very small space and impossible for the seed to lodge here.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 76
Incorrect
-
During a case presentation, a 26 year old is said to have fractured his pelvis and shattered his coccyx following a motorbike accident. It is mentioned that he is likely to have lacerated his middle sacral artery from this kind of injury. Where does the middle sacral artery branch from?
Your Answer: Common iliac artery
Correct Answer: Abdominal aorta
Explanation:The middle sacral artery arises from behind the aorta a little above the point of its bifurcation to descend down in front of L4,5, the sacrum and coccyx.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 77
Correct
-
A 35-year-old ultra marathon runner becomes severely dehydrated and collapses. This patient most likely has:
Your Answer: Decreased baroreceptor firing rate
Explanation:Baroreceptors are sensors located in the blood vessels of all vertebrate animals. They sense the blood pressure and relay the information to the brain, so that a proper blood pressure can be maintained. Acute dehydration results in decreased plasma volume and increased plasma osmolarity, since more water than salt is lost in sweat. The decrease in plasma volume leads to an inhibition of the baroreceptors and a lower firing rate. The increase in plasma osmolarity leads to increased ADH secretion and high plasma ADH levels, which increases water permeability of collecting duct cells. Therefore more water is reabsorbed by the kidneys and renal water excretion is low.
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This question is part of the following fields:
- Physiology
- Renal
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Question 78
Incorrect
-
Where is factor VIII predominantly synthesised?
Your Answer: Hepatocytes
Correct Answer: Vascular endothelium
Explanation:Factor VIII is an important part of the coagulation cascade. Deficiency causes haemophilia A. It is synthesised predominantly by the vascular endothelium and is not affected by liver disease. In the circulation it is bound to von Willebrand factor and it forms a stable complex with it. It is activated by thrombin or factor Xa and acts as a co factor to factor IXa to activate factor X which is a co factor to factor Va. Thrombin cleaves fibrinogen in fibrin and forms a meshwork to trap RBC and platelets to form a clot.
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This question is part of the following fields:
- General
- Physiology
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Question 79
Correct
-
A surgeon performing a Whipple's procedure, that involves mobilizing the head of the pancreases, accidentally injured a structure immediately posterior to the neck of the pancreases which bled out. Which structure is most likely to have been injured?
Your Answer: Superior mesenteric artery
Explanation:The splenic vein runs behind the pancreas, receives the inferior mesenteric vein and joins the superior mesenteric vein to form the portal vein behind the pancreatic neck.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 80
Correct
-
A pedestrian sustained a left fibula fractured following a hit-and-run. X-rays showed that there was a transverse fracture of the upper end of the fibula. It was manifested clinically by inability to flex his foot at the ankle joint plus weak extension of the phalanges. What nerve is suspected to be injured in such a case?
Your Answer: Deep peroneal
Explanation:The deep peroneal nerve supplies the muscles allowing for flexion of the foot at the ankle joint, namely the tibialis anterior and peroneus tertius muscles. The peroneus tertius, peroneus brevis, and peroneus longus evert the foot, whereas the tibialis anterior and tibialis posterior invert the foot. Fibres of the deep peroneal nerve originate from L4, L5, and S1.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 81
Incorrect
-
A 50-year old gentleman who suffered a stroke was brought to the emergency department by his relatives. The patient however denied the presence of paralysis of his left upper and lower limbs. What is the most likely site of the lesion in this patient?
Your Answer: Right precentral gyrus
Correct Answer: Right posterior parietal cortex
Explanation:A large injury to the non-dominant parietal cortex can make the patient neglect or refuse to acknowledge the presence of paralysis on the contralateral side. This can also involve the perception of the external world. Smaller injuries in this area which involve the precentral gyrus (primary motor cortex) or postcentral gyrus (primary sensory cortex) cause contralateral spastic paralysis or contralateral loss of tactile sensation respectively. A lesion in posterior inferior gyrus of the dominant frontal lobe results in motor aphasia. Involvement of the posterior superior gyrus of the dominant frontal lobe produces sensory aphasia.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 82
Correct
-
A textbook of cardiac surgery explains that while doing a left pneumonectomy, a surgeon must be careful to avoid injury to a vital structure that leaves an impression on the mediastinal surface of the left lung. Which structure is it referring to?
Your Answer: Aortic arch
Explanation:Structures that leave an impression on the mediastinal surface of the left lung include: the oesophagus, subclavian artery, brachiocephalic vein, first rib, thymus, the heart, the diaphragm, descending aorta and arch of the aorta. The other structures form an impression on the mediastinal aspect of the right lung.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 83
Correct
-
A 4-year-old child was brought to a paediatrician for consult due to a palpable mass in his abdomen. The child has poor appetite and regularly complains of abdominal pain. The child was worked up and diagnosed with a tumour. What is the most likely diagnosis ?
Your Answer: Nephroblastoma
Explanation:Nephroblastoma is also known as Wilms’ tumour. It is a cancer of the kidneys that typically occurs in children. The median age of diagnose is approximately 3.5 years. With the current treatment, approximately 80-90% of children with Wilms’ tumour survive.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 84
Correct
-
Which of the following is likely to induce secretion of glucagon?
Your Answer: Low serum concentration of glucose
Explanation:The most potent stimulus for secretion of glucagon is hypoglycaemia whereas hyperglycaemia is a stimulus for insulin release. Glucagon secretion also occurs in response to high levels of amino acids. Somatostatin inhibits glucagon secretion. Parasympathetic stimulation increases pancreatic acinar secretion, but not of α-cells.
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This question is part of the following fields:
- Endocrinology
- Physiology
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Question 85
Correct
-
A 34-year-old woman with pelvic inflammatory disease is administered ceftriaxone. The subclass of antibiotics that ceftriaxone belongs to is:
Your Answer: Third-generation cephalosporins
Explanation:Ceftriaxone is a third-generation cephalosporin antibiotic. It has a broad spectrum of activity against Gram-positive and Gram-negative bacteria. Its indications include middle ear infections, endocarditis, meningitis, pneumonia, bone and joint infections, intra-abdominal infections, skin infections, urinary tract infections, gonorrhoea, and pelvic inflammatory disease.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 86
Correct
-
The left lateral pterygoid muscle is one of the muscles of mastication. When acting alone, it will shift the mandible towards which direction?
Your Answer: Laterally, to the right
Explanation:The lateral pterygoid or external pterygoid is a muscle of mastication with two heads. It lies superiorly to the medial pterygoid. When acting alone, it will shift the mandible laterally and to the right.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 87
Correct
-
A 30-year-old woman feels thirsty. This thirst is probably due to:
Your Answer: Increased level of angiotensin II
Explanation:Thirst is the basic need or instinct to drink. It arises from a lack of fluids and/or an increase in the concentration of certain osmolites such as salt. If the water volume of the body falls below a certain threshold or the osmolite concentration becomes too high, the brain signals thirst. Excessive thirst, known as polydipsia, along with excessive urination, known as polyuria, may be an indication of diabetes. Angiotensin II is a hormone that is a powerful dipsogen (i.e. it stimulates thirst) that acts via the subfornical organ. It increases secretion of ADH in the posterior pituitary and secretion of ACTH in the anterior pituitary.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 88
Incorrect
-
Skeletal muscle fibres are divided into two basic types, type I (slow-twitch fibres) and type II (fast-twitch fibres). Fast muscle fibres do which of the following:
Your Answer: Have lots of myoglobin
Correct Answer: Use anaerobic metabolism
Explanation:Skeletal muscles are divided into two types:
1) type I also known as the slow twitch fibres. They use oxygen for their metabolism and as a result they have a high endurance potential. To support this they have abundant mitochondria and myoglobin, so they appear red/dark.
2) type II fibres also called fast twitch fibres, are low endurance fibres used during anaerobic metabolism. They are required for short bursts of strength and cannot sustain contractions for long periods of time.
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This question is part of the following fields:
- General
- Physiology
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Question 89
Incorrect
-
A 37-year-old woman with a history of rheumatic heart disease presents with 10 days recurrent low fever. Patient underwent laboratory work up and was diagnosed with infective endocarditis. What is the most likely organism that caused the infective endocarditis in this patient?
Your Answer: Staphylococcus aureus
Correct Answer: Streptococcus viridans
Explanation:Subacute bacterial endocarditis is often due to streptococci of low virulence, mainly streptococcus viridans. It is a mild to moderate illness which progresses slowly over weeks and months (>2weeks) and has low propensity to hematogenously seed to extracardiac sites.
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This question is part of the following fields:
- Microbiology
- Pathology
-
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Question 90
Correct
-
Question 91
Incorrect
-
A 55-year-old woman died 3 years after a cardiac transplant due to worsening congestive heart failure. Autopsy revealed diffuse hyperplasia of the vascular intima involving the entire length of the coronary arteries. The most probable cause of deterioration of the cardiac function is:
Your Answer: Constrictive pericarditis
Correct Answer: Coronary atherosclerosis
Explanation:Allograft coronary artery disease (CAD) can begin right after the transplant and is the major cause of later death in cardiac transplant recipients. This form of atherosclerosis progresses quickly resulting in allograft failure. Due to lack of premonitory symptoms CAD may lead to sudden death.
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This question is part of the following fields:
- Cardiovascular
- Pathology
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Question 92
Incorrect
-
Following a lacerating injury along the anterior border of the trapezius muscle in the neck, a man has the point of his shoulder (scapula) sagging and he has difficulty with full abduction of his arm. Which nerve is most likely injured?
Your Answer: Axillary
Correct Answer: Accessory (cranial nerve XI)
Explanation:Injury to the accessory nerve denervates the trapezius muscle so that the person will no longer be able to raise the acromion of the shoulder. The dorsal scapular nerve supplies the rhomboids i.e. major and minor and the levator scapulae so that injury to this nerve weakens retraction of the scapula. The greater occipital nerve is responsible for sensation of the posterior scalp. The axillary nerve innervates the deltoid muscle which is responsible for abduction of the arm and the suprascapular nerve is responsible for rotating the humerus laterally. Cutaneous nerves supply the skin.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 93
Correct
-
The orbicularis oculi us a muscle that closes the eyelids. What is the motor innervation of this muscle?
Your Answer: A branch of a nerve that exits through the stylomastoid foramen
Explanation:The orbicularis oculi is a muscle in the face that closes the eyelids. It is supplied by zygomatic branch of the facial nerve (cranial nerve VII), which exits through the stylomastoid foramen.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 94
Correct
-
Where is the foramen ovale located?
Your Answer: Sphenoid
Explanation:The foramen ovale is an oval shaped opening in the middle cranial fossa located at the posterior base of the greater wing of the sphenoid bone, lateral to the lingula. It transmits the mandibular division of the trigeminal nerve (CN Vc), accessory meningeal artery, emissary veins between the cavernous sinuses and pterygoid plexus, otic ganglion, and occasionally the nervus spinosus and lesser petrosal nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 95
Incorrect
-
A man in his sixties underwent surgery to remove a lump from his axilla. During removal, a nerve originating from the lateral cord of the brachial plexus was damaged. Which nerve is this referring to?
Your Answer: Thoracodorsal
Correct Answer: Lateral pectoral
Explanation:The only branch of the lateral cord of brachial plexus in the options given, is the lateral pectoral nerve. It supplies the pectoralis major muscle and sends a branch to join the medial pectoral nerve forming a loop in front of the first part of the axillary artery.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 96
Correct
-
Which one of the following muscles is innervated by the facial nerve?
Your Answer: Buccinator
Explanation:Buccinator is a muscle of facial expression and is therefore innervated by the facial nerve. The lateral pterygoid, masseter, anterior belly of digastric and temporalis are all muscles of mastication and therefore innervated by the mandibular division of the trigeminal nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck; Neurology
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Question 97
Correct
-
The nutcracker effect of the alimentary canal is described as a nutcracker-like compression caused by the aorta and the superior mesenteric arteries on a certain section of the alimentary canal leading to bowel obstruction. Which of the following parts of the alimentary canal is usually obstructed by this nutcracker compression of the two arteries?
Your Answer: Duodenum
Explanation:The ‘nutcracker effect’ is only seen in one part of the alimentary canal, and that is in the third part of the duodenum. This can happen when the superior mesenteric artery that passes across the duodenum and the aorta, posteriorly to the third part of the duodenum enlarges and starts compressing the duodenum. The result is an obstructed duodenum that inhibits passage of food.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 98
Correct
-
Which organ is responsible for the secretion of enzymes that aid in digestion of complex starches?
Your Answer: Pancreas
Explanation:α-amylase is secreted by the pancreas, which is responsible for hydrolysis of starch, glycogen and other carbohydrates into simpler compounds.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 99
Correct
-
A tumour on the floor of the fourth ventricle is most likely to compress which of the following cranial nerve nuclei?
Your Answer: Abducent
Explanation:The fourth ventricle, is a cavity of the brains ventricular system in which the cerebrospinal fluid is formed. This cavity is located behind the pons and upper half of the medulla oblongata. It extends from the cerebral aqueduct, to its connection to the third ventricle, and to the obex- which is the caudal tip of the fourth ventricle. The floor of the fourth ventricle consists of three parts – superior, intermediate and inferior. This inferior aspect of the floor of the fourth ventricle has the nucleus of the abducens nerve, CN VI which is looped over by the facial nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 100
Correct
-
Tumours derived from all three germ-cell layers in new-borns usually occur in which of the following sites?
Your Answer: Sacrococcygeal area
Explanation:A teratoma is a tumour with tissue or organ components resembling normal derivatives of more than one germ layer. It is derived from all three cell layers. The most common location of teratoma in new-born infants is in the sacrococcygeal area.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 101
Correct
-
When a patient that is less than 21 years of age develops a bone tumour. What is the most common benign bone tumour that would be considered in individuals below 21 years?
Your Answer: Osteochondroma
Explanation:Osteochondroma is a benign new bone growth that protrudes from the outer contour of bones and is capped by growing cartilage. Nearly 80% of these lesions are noted before the age of 21 years.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 102
Correct
-
When does the heart rate decrease?
Your Answer: Pressure on the eyeball
Explanation:Various vagotonic manoeuvres (e.g. Valsalva manoeuvre, carotid sinus massage, pressure on eyeballs, ice-water facial immersion, swallowing of ice-cold water) result in increased parasympathetic tone through the vagus nerve which results in a decrease in heart rate. These manoeuvres may be clinically useful in terminating supraventricular arrhythmias.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 103
Correct
-
Which of the following factors will not affect the wound healing process in a young women who suffered serious burns to her chest and hands?
Your Answer: Vitamin A deficiency
Explanation:Healing can be sped-up or slowed down due to various reasons: 1. blood supply, 2. infection, 3. denervation, 4. collection of blood/hematoma, 5. mechanical stress, 6. foreign body, 7. techniques used during surgery and 8. dressing of the wound. Other systemic factors include 1. nutrition e.g. deficiency of zinc, vitamin C, protein deficiency, 2. metabolic status, 3. circulatory status and 4. hormonal influence
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 104
Incorrect
-
A 47-year old-woman diagnosed with pancreatitis presented to the emergency department complaining of a worsening shortness of breath, fever, agitation and cough. Oxygen saturation was 67% in room air. Her respiratory status continued to deteriorate therefore she was intubated. She was admitted to the intensive care unit for management. Chest X-ray demonstrated bilateral perihilar opacities. The patient failed conventional treatment and died several days later. At autopsy, the lung shows growth of type 2 pneumocytes and thickened alveolar walls. What is the most probable diagnosis?
Your Answer: Bronchiectasis
Correct Answer: Adult respiratory distress syndrome
Explanation:Acute (or adult) respiratory distress syndrome (ARDS) is a life-threatening lung condition characterised by a non-cardiogenic pulmonary oedema that leads to acute respiratory failure. The most common risk factors for ARDS include trauma with direct lung injury, sepsis, pneumonia, pancreatitis, burns, drug overdose, massive blood transfusion and shock. Acute onset of dyspnoea with hypoxemia, anxiety and agitation is typical. Chest X ray most commonly demonstrates bilateral pulmonary infiltrates. Histological changes include the exudative, proliferative and fibrotic phase. ARDS is mainly a clinical diagnosis.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 105
Incorrect
-
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: Pulmonary vasodilatation
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 106
Correct
-
The superior pancreaticoduodenal artery, the artery that supplies blood to the pancreas and the duodenum, is a branch of the:
Your Answer: Gastroduodenal artery
Explanation:The superior pancreaticoduodenal artery together with the right gastroepiploic artery form the two branches of the gastroduodenal artery which divides at the lower border of the duodenum.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 107
Incorrect
-
Which of the following is NOT true regarding malignant hyperpyrexia
Your Answer: It occurs in 1 in 150,000
Correct Answer: It can be caused by nitrous oxide
Explanation:Malignant hyerpyrexia occurs in 1 in 150,000. All inhalational anaesthetic agents and suxamethonium, except nitrous oxide can cause malignant hyperpyrexia.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 108
Correct
-
A 25 year-old female medical student presents with fever, lack of appetite, rashes, sore throat and lymphadenopathy. Peripheral smear shows atypical lymphocytes. Which is the most likely organism responsible for this patient's condition?
Your Answer: Epstein–Barr virus
Explanation:Epstein-Barr virus is in the herpes family of viruses and most people will become infected with EBV sometime during their lives. EBV commonly causes infectious mononucleosis, or mono, a contagious viral illness that initially attacks the lymph nodes in the neck and throat. When these tissues become less effective in fighting infection, sore throats, swelling of the nodes and fever may result.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 109
Correct
-
An 18 year-old with an iron deficient diet was prescribed an iron supplement by her GP. Lack of iron often results in:
Your Answer: Hypochromic anaemia
Explanation:Iron deficiency anaemia is the most common type of anaemia. It can occur due to deficiency of iron from decreased intake, increased loss or inadequate absorption. An MCV less than 80 will indicated iron deficiency anaemia. On the smear the RBCs will be microcytic hypochromic and will also show poikilocytosis. Iron profile tests are important to make a diagnosis. Clinically the patient will be pale and lethargic.
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This question is part of the following fields:
- General
- Physiology
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Question 110
Correct
-
A sexually active 21 year old man presents with the history of dysuria for the past 3 days. Urine culture confirmed Neisseria gonorrhoeae and smear showed abundant neutrophils. Which of the following mediators is responsible for causing diapedesis of the neutrophils to reach the site of infection?
Your Answer: Complement C5a
Explanation:C5a is part of the complement cascade and is released frim the complement C5. It acts as a chemotactic factor for neutrophils. Other chemotactic mediators are TNF, leukotrienes and bacterial products.
Bradykinin is associated with the production of pain and vasodilation.
Hageman factor is a clotting factor.
Histamine causes vasodilation.
C3B causes opsonisation.
IL-6 and IL-12 are inflammatory mediators causing B cell maturation and mediating inflammation and prostaglandins are involved with pain, increasing cell permeability and vasodilation.
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This question is part of the following fields:
- Inflammation & Immunology; Urology
- Pathology
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Question 111
Incorrect
-
A 50 year old woman presented with excessive bleeding after an inguinal hernia repair. Labs are suggestive of a primary haemostasis defect. Deficiency of which of the following is most likely to cause it?
Your Answer: Protein C
Correct Answer: Platelets
Explanation:Primary haemostatic control means the first line of defence against immediate bleeding. This is carried out by the platelets. They immediately form a haemostatic plug at the site of injury. Coagulation starts within 20s after an injury to the blood vessel which damage the endothelial cells. Secondary haemostasis follows which includes activation of the coagulation factors to form fibrin strands which mesh together forming the platelet plug. Platelets interact with platelet collagen receptor, glycoprotein Ia/IIa and to collagen fibres in the vascular endothelium. This adhesion is mediated by von Willebrand factor (vWF), which forms links between the platelet glycoprotein Ib/IX/V and collagen fibrils. The platelets are then activated and release the contents of their granules into the plasma, in turn activating other platelets and white blood cells.
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This question is part of the following fields:
- General
- Physiology
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Question 112
Incorrect
-
The renal cortex and medulla, if seen under the microscope, is lacking one of the following:
Your Answer: A basement membrane
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 113
Correct
-
Which muscle originates from the common flexor tendon of the forearm?
Your Answer: Flexor digitorum superficialis
Explanation:The medial epicondyle of the humerus is the site of origin of this group of muscles of the forearm. It originates from the medial epicondyle of the humerus by a common tendon. Fibres from the deep fascia of the forearm, near the elbow and septa, pass from this fascia between the muscles. These muscles include the pronator teres, palmaris longus, flexor carpi radialis, flexor carpi ulnaris and flexor digitorum superficialis.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 114
Correct
-
A 62-year-old male smoker, presented with shortness of breath, chronic cough and haemoptysis over the last three months. He has developed a fat pad in the base of his neck, rounded face, acne and osteoporosis. Which of the following is the most likely pulmonary disease that is causing these symptoms and findings?
Your Answer: Small-cell anaplastic carcinoma
Explanation:Small cell lung cancer is a highly aggressive form of lung cancer. It is thought to originate from neuroendocrine cells in the bronchus called Feyrter cells and is often associated to ectopic production of hormones like ADH and ACTH that result in paraneoplastic syndromes and Cushing’s syndrome.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 115
Correct
-
Following a bee sting, a women develops a 2cm red, raised, swollen lesion at the site of the sting . Which of the following findings is likely to be seen in this lesion?
Your Answer: Vasodilation
Explanation:Inflammation is the immediate response of the body towards infections or irritations. The cardinal signs of inflammation are 1. redness/rubor, 2. tumour/swelling, 3.dolar/pain, 4.calor/heat and organ dysfunction (function laesa). Inflammation has 2 components; vascular and cellular. Blood vessels dilate upstream of the inflamed area leading to the rubor and calor and constrict downstream, increasing pressure and causing fluid to leak out of the capillary, resulting in swelling. The cellular component includes infiltration by neutrophils. Leukocyte arrival and functions include; 1. margination: cells marginated from the centre to the periphery of the vessel, 2. rolling: selectins are upregulated on the vessel walls, 3. adhesion: upregulation of the adhesion molecules ICAM and VCAM on the endothelium interact with integrins on the leukocytes resulting in adhesion, 4. diapedesis and chemotaxis: diapedesis is the transmigration of the leukocyte across the endothelium of the capillary and towards a chemotactic product and 5. phagocytosis: engulfing the offending substance/cell.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 116
Incorrect
-
A 45-year old male, who was a chronic smoker presented to the clinic with backache and dry, incessant cough. On examination, he was found to have raised blood pressure, purplish striae on his abdomen, truncal obesity and tenderness over the lower thoracic spine. These findings are suggestive of which condition?
Your Answer: 21-hydroxylase enzyme deficiency
Correct Answer: Small-cell anaplastic (oat cell) carcinoma
Explanation:The symptoms suggest Cushing syndrome due to increased glucocorticoid levels. One cause of Cushing syndrome is ectopic production of adrenocorticotrophic hormone from oat cell carcinoma. As oat cell carcinoma is known to be highly metastatic, the tenderness in lower back could represent metastatic involvement.
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This question is part of the following fields:
- Endocrine
- Pathology
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Question 117
Incorrect
-
Endometrial hyperplasia is most likely to be associated with which of the following conditions?
Your Answer: Krukenberg tumour
Correct 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 118
Correct
-
A 42 year old women presents with end stage renal failure and is prepared to receive a kidney from her husband. HLA testing showed that they are not a 100% match and she is given immunosuppressant therapy for this. Three months later when her renal function tests were performed she showed signs of deteriorating renal function, with decreased renal output, proteinuria of +++ and RBCs in the urine. She was given antilymphocyte globulins and her condition reversed. What type of graft did this patient receive?
Your Answer: Allograft
Explanation:Allograft describes a graft between two of the same species. As the donor and the recipients are history-incompatible, rejection of the graft is common and is controlled by immunosuppressive drug therapy. Isograft and syngraft are synonymous and referred to a graft transferred between genetically identical individuals e.g. identical twins. In this case rejection is rare as they are history-compatible.
Autograft refers to transfer of one part of the body to another location.
Xenograft is transfer of tissue from another species e.g. pig to human in valve replacement surgeries and rejection is very high.
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This question is part of the following fields:
- Inflammation & Immunology; Renal
- Pathology
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Question 119
Incorrect
-
A 28 years old women presents with a history of chronic cough with fever for the past 2 months. A chest x ray revealed a diffuse bilateral reticulonodular pattern. A transbronchial biopsy was performed and histological examination showed focal areas of inflammation with epithelioid macrophages, Langhans cells and lymphocytes. Which of the immune reaction is responsible for this?
Your Answer: Type II hypersensitivity
Correct Answer: Type IV hypersensitivity
Explanation:A reactivated tuberculosis with granuloma formation is characteristic of type IV reaction. It is also called a delayed type of hypersensitivity reaction and takes around 2-8 days to deliver. It is a cell mediated response with the involvement of CD8 and CD4 cells and the release of IL-1 from macrophages that further activate these CD cells.
Granulomatous reactions are mostly cell-mediated.
Type I reactions are allergic and anaphylactic reactions and type II are complement-mediated immune reactions.
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This question is part of the following fields:
- Inflammation & Immunology; Respiratory
- Pathology
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Question 120
Correct
-
The thoracic duct :
Your Answer: varies in length from 38 to 45 cm
Explanation:The thoracic duct is the main drainage of lymph in the body. It varies in length from 38 to 45 cm and extends from the second lumbar vertebra to the root of the neck.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 121
Incorrect
-
A victim of mob justice was brought to the A & E with a stab wound in the anterior chest 2 cm lateral to the left sternal border. He underwent an emergency thoracotomy that revealed clots in the pericardium, with a puncture wound in the right ventricle. To evacuate the clots from the pericardial cavity the surgeon slipped his hand behind the heart at its apex. He extended his finger upwards until its tip was stopped by a line of pericardial reflection which forms the:
Your Answer: Transverse pericardial sinus
Correct Answer: Oblique pericardial sinus
Explanation:Transverse sinus: part of pericardial cavity that is behind the aorta and pulmonary trunk and in front of the superior vena cava separating the outflow vessels from the inflow vessels.
Oblique pericardial sinus: is behind the left atrium where the visceral pericardium reflects onto the pulmonary veins and the inferior vena cava. Sliding a finger under the heart will take you to this space.
Cardiac notch: indentation of the ‘of the heart’ on the superior lobe of the left lung.
Hilar reflection: the reflection of the pleura onto the root of the lung to continue as mediastinal pleura.
Costomediastinal recess: part of the pleural sac where the costal pleura transitions to become the mediastinal pleura.
Sulcus terminalis: a groove between the right atrium and the vena cava
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 122
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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