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  • Question 1 - Which of the following muscles may be affected by a fracture to the...

    Correct

    • Which of the following muscles may be affected by a fracture to the tuberosity on the medial surface of the right navicular bone?

      Your Answer: Tibialis posterior

      Explanation:

      The navicular bone is situated at the medial side of the tarsus, between the talus and the cuneiform bones. Its medial surface presents a rounded tuberosity, the lower part of which gives attachment to part of the tendon of the tibialis posterior.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      12.8
      Seconds
  • Question 2 - Which ectopic tissue is usually contained in the Meckel's diverticulum? ...

    Correct

    • Which ectopic tissue is usually contained in the Meckel's diverticulum?

      Your Answer: Gastric

      Explanation:

      The Meckel’s diverticulum is a vestigial remnant of the omphalomesenteric duct. This structure is also referred to as the vitelline and contains two types of ectopic tissue, namely; gastric and pancreatic.

    • This question is part of the following fields:

      • Anatomy
      • Embryology
      2.9
      Seconds
  • Question 3 - A 60-year old gentleman visited his general practitioner complaining of high grade fever...

    Correct

    • A 60-year old gentleman visited his general practitioner complaining of high grade fever for 7 days and a dull, aching pain in his left lumbar region. On enquiry, he admitted to having a burning sensation while passing urine. His blood results showed an elevated white blood cell count with a left shift. In his condition, which is the most characteristic finding on urine examination?

      Your Answer: White blood cell casts

      Explanation:

      Tubulointerstitial nephritis is the term given to primary injury to renal tubules and the renal interstitium, which ultimately results in a decline in renal function. Acute tubulointerstitial nephritis (acute pyelonephritis) is often seen as a result of infection or drug reactions. The most characteristic feature of this condition on urine analysis is the presence of white blood cell casts.

    • This question is part of the following fields:

      • Pathology
      • Renal
      11.9
      Seconds
  • Question 4 - The neurotransmitters adrenaline, noradrenaline and dopamine are derived from which amino acid? ...

    Correct

    • The neurotransmitters adrenaline, noradrenaline and dopamine are derived from which amino acid?

      Your Answer: Tyrosine

      Explanation:

      Tyrosine is the precursor to adrenaline, noradrenaline and dopamine. Tyrosine hydroxylase converts tyrosine to DOPA, which is in turn converted to dopamine, then to noradrenaline and finally adrenaline.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      3.1
      Seconds
  • Question 5 - The Brunner glands secrete an alkaline product that helps maintain an optimal pH...

    Correct

    • The Brunner glands secrete an alkaline product that helps maintain an optimal pH for pancreatic enzyme activity. Where are these glands located?

      Your Answer: Submucosa of the duodeneum

      Explanation:

      The Brunner glands are located in the submucosa of the duodenum. These glands are connected to the interstitial lumen by ducts that open into certain crypts. They secrete an alkaline product that protects the duodenal mucosa from the acidic chyme and helps achieve an optimal pH for the enzymes.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      12.7
      Seconds
  • Question 6 - A 45-year old lady underwent biopsy of a soft, fleshy mass involving her...

    Correct

    • A 45-year old lady underwent biopsy of a soft, fleshy mass involving her left breast. The biopsy showed lymphoid stroma with minimal fibrosis, surrounding sheets of large vesicular cells with frequent mitoses. Which condition is she most likely suffering from?

      Your Answer: Medullary carcinoma of breast

      Explanation:

      Medullary carcinoma is a malignant tumour of the breast with well-defined boundaries and accounts for 5% of all breast cancers. Other special features include a larger size of the neoplastic cells and presence of lymphoid cells at tumour edge. Differential diagnosis includes invasive ductal carcinoma. Prognosis is usually good.

    • This question is part of the following fields:

      • Pathology
      • Women's Health
      40.9
      Seconds
  • Question 7 - A 27 year old women works in a dry-cleaning shop. She was exposed...

    Correct

    • A 27 year old women works in a dry-cleaning shop. She was exposed to massive amounts of carbon tetrachloride on her skin as well as inhaled. Which of the following organs is most susceptible to damage?

      Your Answer: Liver

      Explanation:

      Carbon tetrachloride (CCl4) is a common agent used in the dry cleaning industry and is thought to cause the formation of free radicals. It causes rapid breakdown of the endoplasmic reticulum due to decomposition of lipids and severe liver cell injury. Within less than 30 mins, hepatic protein synthesis declines, lipid export is reduced due to lack of apoprotein and there is an influx of calcium and cell death.

    • This question is part of the following fields:

      • Cell Injury & Wound Healing
      • Pathology
      6
      Seconds
  • Question 8 - During cardiac catheterisation in a 20-year old man, the following data is obtained:...

    Correct

    • During cardiac catheterisation in a 20-year old man, the following data is obtained: Pressure (mmHg), O2 saturation (%) Right atrium 7 (N = 5) 90 (N = 75), Right ventricle 35/7 (N = 25/5) 90 (N = 75), Pulmonary artery 35/8 (N = 25/15), 90 (N = 75), Left atrium 7 (N = 9) 95 (N = 95), Left ventricle 110/7 (N = 110/9) 95 (N = 95), Aorta 110/75 (N = 110/75) 95 (N = 95) where N = Normal value. What is the likely diagnosis?

      Your Answer: Atrial septal defect

      Explanation:

      A congenital heart disease, ASD or atrial septal defect leads to a communication between the right and left atria due to a defect in the interatrial septum. This leads to mixing of arterial and venous blood from the right and left side of the heart. The hemodynamic significance of this defect depends on the presence of shunting of blood. Normally, the left side of the heart has higher pressure than the right as the left side has to pump blood throughout the body. A large ASD (> 9 mm) will result in a clinically significant left-to-right shunt, causing volume overload of the right atrium and ventricle, eventually leading to heart failure. Cardiac catheterization would reveal very high oxygen saturation in the right atrium, right ventricle and pulmonary artery. Eventually, the left-to-right shunt will lead to pulmonary hypertension and increased afterload in the right ventricle, along with the increased preload due to the shunted blood. This will either cause right ventricular failure, or raise the pressure in the right side of the heart to equal or more than that in the left. Elevation of right atrial pressure to that of left atrial pressure would thus lead to diminishing or complete cessation of the shunt. If left uncorrected, there will be reversal of the shunt, known as Eisenmenger syndrome, resulting in clinical signs of cyanosis as the oxygen-poor blood form right side of the heart will mix with the blood in left side and reach the peripheral vascular system.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      26
      Seconds
  • Question 9 - Following a posterolateral thoracotomy, a surgeon may wish to infiltrate local anaesthetic above...

    Incorrect

    • Following a posterolateral thoracotomy, a surgeon may wish to infiltrate local anaesthetic above and below the incision to block the nerves supplying the thoracic wall. This wall is innervated by?

      Your Answer: Dorsal primary rami

      Correct Answer: Intercostal nerves

      Explanation:

      Intercostal nerves are the ventral primary rami of spinal nerves T1–T11. They give branches which supply the thoracic wall.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      15
      Seconds
  • Question 10 - A 44-year old man, who was euthyroid underwent thyroidectomy following neoplastic cells found...

    Correct

    • A 44-year old man, who was euthyroid underwent thyroidectomy following neoplastic cells found on fine-needle aspiration. Frozen section of multiple thyroid masses showed malignant neoplasm of polygonal cells in nests. The neoplasm also showed presence of amyloid which was positive with Congo-red staining. Immunoperoxidase staining for calcitonin was also positive. Chest X-ray revealed no abnormality. However, his blood pressure was found to be raised, and his serum ionised calcium was high. What is the likely diagnosis?

      Your Answer: Multiple endocrine neoplasia type IIA

      Explanation:

      MEN (Multiple Endocrine Neoplasia) syndromes are a group of three separate familial disease which consists of adenomatous hyperplasia and neoplasia in several endocrine glands. All three conditions are inherited as an autosomal dominant trait, with a single gene producing multiple effects. MEN IIA is characterized by medullary carcinoma of the thyroid, pheochromocytoma and hyperparathyroidism. It should be suspected in patients with bilateral pheochromocytoma, a familial history of MEN, or at least two characteristic endocrine manifestations. Genetic testing is used to confirm the diagnosis. Early diagnosis is crucial to aid in complete excision of the localized tumour. Pheochromocytomas can be detected by plasma free metanephrines and fractionated urinary catecholamines, particularly adrenaline (epinephrine).

      Imaging studies such as computed tomography or magnetic resonance imaging might also prove useful. Hyperparathyroidism is diagnosed by the standard finding of hypercalcaemia, hypophosphatemia and an increased parathyroid hormone level. Once MEN IIA syndrome is identified in any patient, it is recommended that his or her first-degree relatives and any other symptomatic also undergo genetic testing. Relatives should be subjected to annual screening for hyperparathyroidism and pheochromocytoma beginning in early childhood and continue indefinitely. Serum calcium levels help in screening for hyperparathyroidism. Similarly, screening for pheochromocytoma is by history, measurement of the blood pressure and laboratory testing.

    • This question is part of the following fields:

      • Endocrine
      • Pathology
      23.5
      Seconds
  • Question 11 - This structure divides the space between the lens and the cornea into the...

    Correct

    • This structure divides the space between the lens and the cornea into the anterior and posterior chambers of the eye:

      Your Answer: The iris

      Explanation:

      The iris divides the space between the lens and the cornea into an anterior and a posterior chamber. The anterior cavity is filled with watery aqueous fluid, and the posterior cavity with a gel-like vitreous fluid. The anterior chamber of the eye is bounded in front by the posterior surface of the cornea; behind by the front of the iris and the central part of the lens. The posterior chamber is a narrow gap behind the peripheral part of the iris and in front of the suspensory ligament of the lens and the ciliary processes.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      32.2
      Seconds
  • Question 12 - A diabetic 58-year-old man, after the injection of radiographic contrast, has a decreased...

    Correct

    • A diabetic 58-year-old man, after the injection of radiographic contrast, has a decreased urine output and decreased level of consciousness. Which of the following conditions has he most likely developed

      Your Answer: Acute tubular necrosis

      Explanation:

      Acute tubular necrosis (ATN) involves damage to the tubule cells of the kidneys and is the most common cause of acute kidney injury. ATN in the majority of the cases is caused by ischaemia of the kidneys due to lack of perfusion and oxygenation but it may also occur due to poison or harmful substance. Contrast used for radiology may cause ATN in patients with several risk factors e.g. diabetic nephropathy. Symptoms may include oliguria, nausea, fluid retention, fatigue and decreased consciousness.

    • This question is part of the following fields:

      • Pathology
      • Renal
      14.1
      Seconds
  • Question 13 - Which statement is true about the inferior sagittal sinus? ...

    Incorrect

    • Which statement is true about the inferior sagittal sinus?

      Your Answer: It drains into the transverse sinus

      Correct Answer: Is formed between two layers of meningeal dura

      Explanation:

      The inferior sagittal sinus is also known as the inferior longitudinal sinus. It courses along the inferior border of the falx cerebri, superior to the corpus callosum. It is cylindrical in shape and increases in size as it passes backward ending in the straight sinus. It receives blood from the deep and medial aspects of the cerebral hemispheres and drains into the straight sinus.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      14.4
      Seconds
  • Question 14 - Which of the following can lead to haemolytic anaemia? ...

    Incorrect

    • Which of the following can lead to haemolytic anaemia?

      Your Answer: Bone marrow aplasia

      Correct Answer: Presence of haemoglobin S

      Explanation:

      Haemoglobin S is an abnormal type of haemoglobin seen in sickle cell anaemia. This allows for the haemoglobin to crystalize within the RBC upon exposure to low partial pressures of oxygen. This results in rupture of the RBCs as they pass through microcirculation, especially in the spleen. This can cause blockage of the vessel down stream and ischaemic death of tissues, accompanied by severe pain.

    • This question is part of the following fields:

      • General
      • Physiology
      16.6
      Seconds
  • Question 15 - A 59-year-old man was brought to the emergency department by his family after...

    Correct

    • A 59-year-old man was brought to the emergency department by his family after complaining of sudden, severe upper back pain and a ripping sensation, that radiated to his neck. On arrival, his pulse was weak in one arm compared with the other however his ECG result was normal. Which of the following is most probably the cause of these findings and symptoms?

      Your Answer: Acute aortic dissection

      Explanation:

      Acute aortic dissection is a serious condition in which the inner layer of the aorta tears and the blood flows in between the inner and middle layers of the aorta causing their separation (dissection). Aortic dissection can lead to rupture or decreased blood flow to organs. Clinical manifestations most often include the sudden onset of severe, tearing or ripping chest pain that can radiate to the shoulder, back or neck; syncope; altered mental status; dyspnoea; pale skin; stroke symptoms etc. The diagnosis of acute aortic dissection is based on clinical findings, imaging studies, electrocardiography and laboratory analysis.

    • This question is part of the following fields:

      • Cardiovascular
      • Pathology
      10.1
      Seconds
  • Question 16 - Following nerve injury, paralysis of the quadriceps femoris muscle occurs. Which of the...

    Correct

    • Following nerve injury, paralysis of the quadriceps femoris muscle occurs. Which of the following movements will be affected?

      Your Answer: Extension of the leg

      Explanation:

      The quadriceps muscle is a great extensor of the thigh. Therefore, following nerve injury or cutting nerve supply to the quadriceps will affect extension of the thigh

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      19.5
      Seconds
  • Question 17 - Basal Metabolic Rate (BMR) will most likely be reduced by which of the...

    Correct

    • Basal Metabolic Rate (BMR) will most likely be reduced by which of the following?

      Your Answer: Decrease in body temperature

      Explanation:

      The basal metabolic rate (BMR) is defined as the rate of calorie consumption after an overnight fast, in the absence of any muscular activity, with the patient in a restful state. Various factors affect the BMR including weight, body surface area and age. The BMR is 30 kcal/m2 per hour at birth; at age 2, the rate is 57 kcal/m2 per hour; and at age 20, 41 kcal/m2 per hour. After this, the BMR decreases by 10% between 20-60 years of age. Women are known to have a 10% lower BMR than men (due to higher fat content). A one-degree change in body temperature leads to a 10% change in BMR in the same direction. However, shivering and increasing ambient temperature brings about a rise in BMR, and so does stress, physical activity, caffeine, theophylline and hyperthyroidism. Also, thermogenesis induced by diet results in increased metabolic rate and hence, BMR should be ideally measured after overnight fasting.

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      5.5
      Seconds
  • Question 18 - The Henderson–Hasselbalch equation describes the derivation of pH as a measure of acidity. According to this equation,...

    Correct

    • The Henderson–Hasselbalch equation describes the derivation of pH as a measure of acidity. According to this equation, the buffering capacity of the system is at maximum when the number of free anions compared with undissociated acid is:

      Your Answer: Equal

      Explanation:

      In 1908, Lawrence Joseph Henderson wrote an equation describing the use of carbonic acid as a buffer solution. Later, Karl Albert Hasselbalch re-expressed that formula in logarithmic terms, resulting in the Henderson–Hasselbalch equation. The equation is also useful for estimating the pH of a buffer solution and finding the equilibrium pH in acid–base reactions. Two equivalent forms of the equation are: pH = pKa + log10 [A–]/[HA] or pH = pKa + log10 [base]/[acid]. Here, pKa is − log10(Ka) where Ka is the acid dissociation constant, that is: pKa = –log10(Ka) = –log10 ([H3 O+][A–]/[HA]) for the reaction: HA + H2 O ≈ A– + H3 O+ In these equations, A– denotes the ionic form of the relevant acid. Bracketed quantities such as [base] and [acid] denote the molar concentration of the quantity enclosed. Maximum buffering capacity is found when pH = pKa or when the number of free anions to undissociated acid is equal and buffer range is considered to be at a pH = pKa ± 1.

    • This question is part of the following fields:

      • Fluids & Electrolytes
      • Physiology
      20.3
      Seconds
  • Question 19 - During an exploratory laparotomy in a 22 year-old man shot in the abdomen,...

    Correct

    • During an exploratory laparotomy in a 22 year-old man shot in the abdomen, the operating doctor discovers the large bowel is perforated. Which of the following characteristics of the bowel enabled the surgeon to identify it as the large bowel?

      Your Answer: Epiploic appendages

      Explanation:

      The large intestine doesn’t have a continuous layer of longitudinal muscle. Instead, it has three strips of longitudinal muscle called taenia coli. The large intestine is covered with omental appendages that are fat filled. It is also folded into sacculations called haustrations. Serosa is a general term for the outermost coat or serous layer of a visceral structure that lies in the body cavities of the abdomen or thorax.

      Complete circular folds are only found in the small intestine.

      Valvulae conniventes or valves of Kerckring are the circular folds which are large valvular flaps projecting into the lumen of the small bowel.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      10.7
      Seconds
  • Question 20 - A patient who has used NSAIDS for many years presents to the A&E...

    Correct

    • A patient who has used NSAIDS for many years presents to the A&E with symptoms of acute haemorrhagic shock. An emergency endoscopy is done that shows that a duodenal ulcer has perforated the posterior wall of the first part of the duodenum. Which artery is most likely to be the cause of the haemorrhage?

      Your Answer: Gastroduodenal

      Explanation:

      The gastroduodenal artery is a branch of the hepatic artery and descends near the pylorus between the first part of the duodenum and the neck of the pancreas to divide at the lower border of the duodenum into the right gastroepiploic and pancreaticoduodenal arteries. Before it divides, it gives off a few branches to the pyloric end of the stomach and to the pancreas. The artery that is most likely involved in this situation is the gastroduodenal artery since it is posterior to the first part of the duodenum.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      8.5
      Seconds
  • Question 21 - What will the destruction of endoplasmic reticulum stop? ...

    Correct

    • What will the destruction of endoplasmic reticulum stop?

      Your Answer: Synthesis of proteins

      Explanation:

      The rough endoplasmic reticulum is the factory for the manufacturing of proteins. It contains ribosomes attached to it and transports proteins that are destined for membranes and secretions. The rough ER is connected to the nuclear envelope and to the cisternae of the Golgi apparatus by vesicles that shuttle between the two compartments.

    • This question is part of the following fields:

      • General
      • Physiology
      4.2
      Seconds
  • Question 22 - What is the most likely condition a new born infant is likely to...

    Correct

    • What is the most likely condition a new born infant is likely to suffer from, if he/she was born with incomplete fusion of the embryonic endocardial cushions?

      Your Answer: An atrioventricular septal defect

      Explanation:

      The endocardial cushions in the heart are the mesenchymal tissue that make up the part of the atrioventricular valves, atrial septum and ventricular septum. An incomplete fusion of these mesenchymal cells can cause an atrioventricular septal defect. The terms endocardial cushion defect, atrioventricular septal defect and common atrioventricular canal defect can be used interchangeably with one another.

    • This question is part of the following fields:

      • Anatomy
      • Embryology
      12.3
      Seconds
  • Question 23 - When the pitch of a sound increases, what is the physiological response seen...

    Incorrect

    • When the pitch of a sound increases, what is the physiological response seen in the listener?

      Your Answer: A decrease in the number of hair cells getting activated

      Correct Answer: The location of maximal basilar membrane displacement moves toward the base of the cochlea

      Explanation:

      An increase in the frequency of sound waves results in a change in the position of maximal displacement of the basilar membrane in the cochlea. Low pitch sound produces maximal displacement towards the cochlear apex and greatest activation of hair cells there. With an increasing pitch, the site of greatest displacement moves towards the cochlear base. However, increased amplitude of displacement, increase in the number of activated hair cells, increased frequency of discharge of units in the auditory nerve and increase in the range of frequencies to which such units respond, are all seen in increases in the intensity or a sound stimulus.

    • This question is part of the following fields:

      • Neurology
      • Physiology
      50.1
      Seconds
  • Question 24 - When a patient that is less than 21 years of age develops a...

    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.

    • This question is part of the following fields:

      • Neoplasia
      • Pathology
      14.4
      Seconds
  • Question 25 - A CT-scan report of a patient with gastric carcinoma shows that the lymph...

    Correct

    • A CT-scan report of a patient with gastric carcinoma shows that the lymph nodes around the coeliac trunk are enlarged. The coeliac trunk:

      Your Answer: Gives rise to the splenic, left gastric and common hepatic arteries

      Explanation:

      The coeliac trunk is a branch of the aorta arising just below the aortic hiatus of the diaphragm to pass nearly horizontally forward to divide into 3 large branches i.e. the left gastric, the hepatic and the splenic arteries. Occasionally it may give off one of the inferior phrenic arteries. It is covered by the lesser omentum and on the right side bordered by the right coeliac ganglion and the cardiac end of the stomach. Inferiorly it is bordered by the upper border of the pancreas and splenic vein. The embryonic midgut is supplied by the superior mesenteric artery.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      8.6
      Seconds
  • Question 26 - A 14 year old girl suffers from haemophilia A and chronic knee pain...

    Correct

    • A 14 year old girl suffers from haemophilia A and chronic knee pain with progressive swelling and deformity over the last 4 years. Test results reveal a significantly reduced factor VIII activity. Which of the following is seen in the knee joint space after an acute painful episode?

      Your Answer: Cholesterol crystals

      Explanation:

      Due to breakdown of the red blood cell membrane in haemophilic patients, cholesterol crystals are formed by the lipids. On the other hand lipofuscin deposition does not occur in haemolysis or haemorrhage. Neutrophil accumulation suggests acute inflammation. Anthracotic pigment is an exogenous carbon pigment that deposits in the lung from dust. Russell bodies are intracellular accumulations of immunoglobins in plasma cells. Curschmann’s spirals and Charcot Leyden crystals are pathognomonic of asthma.

    • This question is part of the following fields:

      • Cell Injury & Wound Healing; Haematology
      • Pathology
      12.1
      Seconds
  • Question 27 - A young girl who presented with a clinical picture of type I hypersensitivity...

    Correct

    • A young girl who presented with a clinical picture of type I hypersensitivity reaction with eosinophilia is most likely to have?

      Your Answer: Liver flukes

      Explanation:

      Usually a parasitic infection will be associated with a type I hypersensitivity reaction.

      Amyloid deposition will not cause an immune reaction.

      Organic dust will lead to a type III hypersensitivity reaction.

      Cell mediated as well as humoral immune mechanism play a part in syphilis, but they are do not specifically cause a type I reaction.

      Malaria is cause by plasmodium and is not cause of a hypersensitivity reaction.

      Atopic dermatitis will not be accompanied by eosinophilia.

    • This question is part of the following fields:

      • Inflammation & Immunology
      • Pathology
      5.3
      Seconds
  • Question 28 - Which muscle is responsible for directing the gaze downward when the eye is...

    Incorrect

    • Which muscle is responsible for directing the gaze downward when the eye is abducted?

      Your Answer: Inferior oblique muscle

      Correct Answer: Inferior rectus muscle

      Explanation:

      The inferior rectus muscle is a muscle in the orbit. As with most of the muscles of the orbit, it is innervated by the inferior division of oculomotor nerve (Cranial Nerve III). It depresses, adducts, and helps laterally rotate the eye.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      3.6
      Seconds
  • Question 29 - The collaborative effort of the lateral pterygoid muscles produces which action on the...

    Correct

    • The collaborative effort of the lateral pterygoid muscles produces which action on the jaw?

      Your Answer: Protrude the mandible

      Explanation:

      The combined effort of the lateral pterygoid muscles results in the protrusion of the mandible. The lateral pterygoid muscle is a muscle of mastication located superiorly to the medial pterygoid muscle and has two heads. The superior head originates on the infratemporal surface and infratemporal crest of the greater wing of the sphenoid bone, and the inferior head on the lateral surface of the lateral pterygoid plate. The insertion of this muscle is on the front margin of the articular disc of the temporomandibular joint. The unilateral contraction of the pterygoid muscle results in the laterotrusion of the mandible. It is important to note that the lateral pterygoid muscle is the only muscle of mastication that can open the jaw.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      7.4
      Seconds
  • Question 30 - Which nodes are most likely to be enlarged in a patient complaining of...

    Correct

    • Which nodes are most likely to be enlarged in a patient complaining of a boil located on the labia majora?

      Your Answer: Superficial inguinal

      Explanation:

      The perineum, external genitalia, the labia majora and scrotum drain to the superficial inguinal lymph nodes. In a man, the testes do not drain to the superficial inguinal lymph nodes but rather travel in the spermatic cord and drain into the lumbar nodes. The lumbar nodes drain the internal pelvic organs. The sacral nodes drain the prostrate gland, uterus, vagina, rectum and posterior pelvic wall and the external iliac nodes in turn drain the lower limb. The internal iliac nodes drain the pelvis and gluteal region.

    • This question is part of the following fields:

      • Anatomy
      • Pelvis
      5.1
      Seconds
  • Question 31 - Action potentials are used extensively by the nervous system to communicate between neurones...

    Correct

    • Action potentials are used extensively by the nervous system to communicate between neurones and muscles or glands. What happens during the activation of a nerve cell membrane?

      Your Answer: Sodium ions flow inward

      Explanation:

      During the generation of an action potential, the membrane gets depolarized which cause the voltage gated sodium channels to open and sodium diffuses inside the neuron, resulting in the membrane potential moving towards a positive value. This positive potential will then open the voltage gated potassium channels and cause more K+ to move out decreasing the membrane potential and restoring the membrane potential to its resting value.

    • This question is part of the following fields:

      • General
      • Physiology
      18.9
      Seconds
  • Question 32 - A patient presents with loss of pain and temperature sensation in the left...

    Correct

    • A patient presents with loss of pain and temperature sensation in the left leg. He is likely to have a lesion involving:

      Your Answer: Right lateral spinothalamic tract

      Explanation:

      The spinothalamic tract is a sensory pathway originating in the spinal cord that transmits information to the thalamus. There are two main parts of the spinothalamic tract: the lateral spinothalamic tract transmits pain and temperature and the anterior spinothalamic tract transmits touch (crude touch). The decussation of this pathway occurs at the level of the spinal cord. Hence, a unilateral lesion of the lateral spinothalamic tract causes contralateral loss of pain and temperature.

    • This question is part of the following fields:

      • Neurology
      • Physiology
      30.7
      Seconds
  • Question 33 - Which of the following is a true statement regarding secretion of gastric acid?...

    Correct

    • Which of the following is a true statement regarding secretion of gastric acid?

      Your Answer: Acetylcholine increases gastric acid secretion

      Explanation:

      Gastric acid secretion is increased by acetylcholine, histamine and gastrin, with the help of cAMP as a secondary messenger. They increase H+ and Cl- secretion by increasing the number of H+/K+ ATPase molecules and Cl- channels. In contrast, gastric acid secretion is decreased by somatostatin, epidermal growth factor and prostaglandins.

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      10.9
      Seconds
  • Question 34 - A 25 year old primi gravida lady was scheduled for a regular antenatal...

    Correct

    • A 25 year old primi gravida lady was scheduled for a regular antenatal check up. During the vaginal exam of this lady, the registrar discovered a malignant growth on the anterior wall of her vagina. Which of the following structures, adjacent to the vagina, is likely to be involved as well?

      Your Answer: Fundus of the bladder

      Explanation:

      The fundus of the bladder is related anatomically to the anterior surface of the vagina and the urethra as well. If there was a malignant growth in the anterior surface of the vagina, then most likely the fundus of the bladder would be involved as well aspotentially the urethra.

    • This question is part of the following fields:

      • Anatomy
      • Pelvis
      10.3
      Seconds
  • Question 35 - Glucose is the most important source of energy for cellular respiration. The transport...

    Correct

    • Glucose is the most important source of energy for cellular respiration. The transport of glucose in the renal tubular cells occurs via:

      Your Answer: Secondary active transport with sodium

      Explanation:

      In 1960, Robert K. Crane presented for the first time his discovery of the sodium-glucose cotransport as the mechanism for glucose absorption. Glucose transport through biological membranes requires specific transport proteins. Transport of glucose through the apical membrane of renal tubular as well as intestinal epithelial cells depends on the presence of secondary active Na+–glucose symporters, SGLT-1 and SGLT-2, which concentrate glucose inside the cells, using the energy provided by co-transport of Na+ ions down their electrochemical gradient.

    • This question is part of the following fields:

      • Physiology
      • Renal
      7.1
      Seconds
  • Question 36 - A 5-year-old child presents with fever and otalgia. Greenish pustular discharge was seen...

    Incorrect

    • A 5-year-old child presents with fever and otalgia. Greenish pustular discharge was seen in his left ear during physical examination. The patient is diagnosed with otitis externa. Which of the following organisms most likely caused the infection?

      Your Answer: Streptococcus pyogenes

      Correct Answer: Pseudomonas aeruginosa

      Explanation:

      P. aeruginosa is a multidrug resistant pathogen recognised for its ubiquity, its advanced antibiotic resistance mechanisms and its association with serious illnesses – especially hospital-acquired infections such as ventilator-associated pneumonia and various septic syndromes. The species name aeruginosa is a Latin word meaning verdigris (copper rust), referring to the blue-green colour of laboratory cultures of the species. This blue-green pigment is a combination of two metabolites of P. aeruginosa, pyocyanin (blue) and pyoverdine (green), which impart the blue-green characteristic colour of cultures.

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      15.5
      Seconds
  • Question 37 - A man in his sixties underwent surgery to remove a lump from his...

    Correct

    • 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: 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.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      8.4
      Seconds
  • Question 38 - Which is the most common benign germ-cell tumour that could occur in a...

    Correct

    • Which is the most common benign germ-cell tumour that could occur in a premenopausal woman?

      Your Answer: Dermoid cyst

      Explanation:

      A dermoid cyst is a teratoma of a cystic nature that contains an array of developmentally mature and solid tissues. Dermoid cysts grow slowly and this type of cystic teratoma is nearly always benign.

    • This question is part of the following fields:

      • Neoplasia
      • Pathology
      14.1
      Seconds
  • Question 39 - The pterygoid plexus receives tributaries from which of the following veins? ...

    Incorrect

    • The pterygoid plexus receives tributaries from which of the following veins?

      Your Answer: Posterior auricular vein

      Correct Answer: Maxillary vein

      Explanation:

      The pterygoid plexus of veins is the main venous component associated with the infratemporal fossa. It receives tributaries corresponding to the branches of the internal maxillary artery. This plexus communicates freely with the anterior facial vein; it also communicates with the cavernous sinus, by branches through the foramen of Vesalius, foramen ovale and foramen lacerum. The (internal) maxillary vein is a short trunk which accompanies the first part of the (internal) maxillary artery. It is formed by a confluence of the veins of the pterygoid plexus and passes backward between the sphenomandibular ligament and the neck of the mandible and unites with the temporal vein to form the posterior facial vein. It carries blood away from the infratemporal fossa.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      11
      Seconds
  • Question 40 - A 62-year-old woman presented to the doctor complaining of spine pain, fatigue and...

    Correct

    • A 62-year-old woman presented to the doctor complaining of spine pain, fatigue and oliguria. She is diagnosed with chronic renal failure. Dipstick testing shows no protein, glucose, nitrite or ketones but a semi-quantitative sulphosalicylic acid test for urine protein is positive. Which of the following is the most probable cause of chronic renal failure in this patient.

      Your Answer: Multiple myeloma

      Explanation:

      Dipstick results are negative because the proteins found in the urine of this patient are not albumin but Bence Jones proteins. A Bence Jones protein is a monoclonal globulin protein commonly detected in patients affected by multiple myeloma. Multiple myeloma is a malignancy of plasma cells characterised by the production of monoclonal immunoglobulin. Symptoms include bone pain, bone fractures, bleeding, neurologic symptoms, fatigue, frequent infections and weight loss.

    • This question is part of the following fields:

      • Pathology
      • Renal
      26.2
      Seconds
  • Question 41 - Infection to all of the following will lead to enlargement of the superficial...

    Correct

    • Infection to all of the following will lead to enlargement of the superficial inguinal lymph nodes, except for:

      Your Answer: Ampulla of the rectum

      Explanation:

      The superficial inguinal lymph nodes form a chain immediately below the inguinal ligament. They receive lymphatic supply from the skin of the penis, scrotum, perineum, buttock and abdominal wall below the level of the umbilicus.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      8.8
      Seconds
  • Question 42 - A week after a renal transplant the patient received antilymphocyte globulins. Shortly after...

    Incorrect

    • A week after a renal transplant the patient received antilymphocyte globulins. Shortly after she developed fever and hypotension. Which of the following mechanisms is involved in this response?

      Your Answer: Type I hypersensitivity

      Correct Answer: Type III hypersensitivity

      Explanation:

      Type III hypersensitivity is characterized by soluble immune complexes which are aggregations of IgG and IgM antibodies with antigens that deposit in different tissues e.g. the skin, joints, kidneys. They can then trigger an immune response by activating the complement cascade. This reaction can take hours to develop and examples include: immuno-complex glomerulonephritis, rheumatoid arthritis, SLE, subacute bacterial endocarditis, arthus reaction and serum sickness.

    • This question is part of the following fields:

      • Inflammation & Immunology
      • Pathology
      9.5
      Seconds
  • Question 43 - A growing tumour is impinging on the lingual artery in the floor of...

    Correct

    • A growing tumour is impinging on the lingual artery in the floor of the mouth. Which structure will experience decreased blood flow?

      Your Answer: The sublingual gland

      Explanation:

      The paired sublingual glands are major salivary glands in the mouth. They are the smallest, most diffuse, and the only unencapsulated major salivary glands. They provide only 3-5% of the total salivary volume. The gland receives its blood supply from the sublingual and submental arteries. The sublingual artery is a branch of the lingual artery, thus damage to the lingual artery will decrease the blood flow to the sublingual gland.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      9.9
      Seconds
  • Question 44 - After severe injury of the upper limb following an accident. The humerus is...

    Correct

    • After severe injury of the upper limb following an accident. The humerus is injured as well as the nerve which innervates the muscles of the anterior compartment of the arm. Which nerve is injured?

      Your Answer: Musculocutaneous

      Explanation:

      The musculoskeletal nerve supplies the muscles of the anterior compartment of the arm including the coracobrachialis, biceps brachii and the greater part of the brachialis. This nerve derives its fibres from the fifth, sixth and seventh cervical nerves and arises from the lateral cord of the brachial plexus. It also provides a branch to the elbow joint.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      7.4
      Seconds
  • Question 45 - Multiple cells were labelled using a fluorescent dye that doesn’t cross the cell...

    Correct

    • Multiple cells were labelled using a fluorescent dye that doesn’t cross the cell membrane. One cell in the middle was bleached with a light that destroys the dye, but the cell soon recovers its stain. The presence of which structures best explains this?

      Your Answer: Gap junctions

      Explanation:

      Gap junctions are attachments between cells that permit intercellular communication e.g. they permit current flow and electrical coupling between myocardial cells. They allow direct electrical transmission among cells and also permit certain substance to pass through as well. They are either homotypic, formed by two identical hemichannels or heterotypic, formed by different hemichannels.

    • This question is part of the following fields:

      • General
      • Physiology
      8.8
      Seconds
  • Question 46 - Which statement is correct regarding coagulation? ...

    Correct

    • Which statement is correct regarding coagulation?

      Your Answer: Thrombin converts fibrinogen to fibrin

      Explanation:

      Coagulation of blood is a complex process and an important part of haemostasis. There are two main pathways related to coagulation: the contact activation pathway/intrinsic pathway and tissue factor/extrinsic pathway. The extrinsic pathway is activated by external trauma that causes blood to escape from the vascular system. This pathway is quicker than the intrinsic pathway and involves factor VII. The intrinsic pathway is activated by trauma inside the vascular system, and initiated by platelets, exposed endothelium, chemicals, or collagen. This pathway is slower than the extrinsic pathway, but more important. It involves factors XII, XI, IX, VIII. Both pathways meet to finish the formation of a clot in what is known as the common pathway. The common pathway involves factors I, II, V, and X. They converge on the common pathway in which activation of prothrombin to thrombin leads to conversion of fibrinogen to fibrin and clot formation.

    • This question is part of the following fields:

      • General
      • Physiology
      22.4
      Seconds
  • Question 47 - During thymectomy the surgeon accidentally nicks a vein that lies just posterior to...

    Incorrect

    • During thymectomy the surgeon accidentally nicks a vein that lies just posterior to the thymus. Which of the following vessels is likely to be injured?

      Your Answer: Right brachiocephalic vein

      Correct Answer: Left brachiocephalic vein

      Explanation:

      The thymus is located superficially in the anterior mediastinum. The left brachiocephalic vein courses through the mediastinum to join the right brachiocephalic vein and form the superior vena cava on the right side of the thorax. The left brachiocephalic vein, being superficial, courses just deep to the thymus so that it may be susceptible to compression by an adjacent tumour. The left pulmonary vein, left bronchial vein and right pulmonary artery are deep, and enter and exit the lung at its root, thus are not near the thymus. The right superior intercostal vein drains the 2nd to the 4th intercostal spaces and drains into the arch of the azygos vein. It is not, therefore, closely related with the thymus.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      21.5
      Seconds
  • Question 48 - Acute respiratory distress syndrome (ARDS) is a medical condition that occurs in critically...

    Correct

    • Acute respiratory distress syndrome (ARDS) is a medical condition that occurs in critically ill patients, and can be triggered by events such as trauma and sepsis. Which of the following variables is most likely to be lower than normal in a patient with ARDS?

      Your Answer: Lung compliance

      Explanation:

      Acute (or Adult) respiratory distress syndrome (ARDS) is a medical condition occurring in critically ill patients characterized by widespread inflammation in the lungs. The development of acute respiratory distress syndrome (ARDS) starts with damage to the alveolar epithelium and vascular endothelium, resulting in increased permeability to plasma and inflammatory cells. These cells pass into the interstitium and alveolar space, resulting in pulmonary oedema. Damage to the surfactant-producing type II cells and the presence of protein-rich fluid in the alveolar space disrupt the production and function of pulmonary surfactant, leading to micro atelectasis and impaired gas exchange. The pathophysiological consequences of lung oedema in ARDS include a decrease in lung volumes, compliance and large intrapulmonary shunts. ARDS may be seen in the setting of pneumonia, sepsis, following trauma, multiple blood transfusions, severe burns, severe pancreatitis, near-drowning, drug reactions, or inhalation injuries.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      37.6
      Seconds
  • Question 49 - The circle of Willis is an arterial anastomosis in the base of the...

    Correct

    • The circle of Willis is an arterial anastomosis in the base of the brain and is one of the cerebrovascular safeguards in the brain. Where is the circle of Willis contained?

      Your Answer: Cisterna basalis

      Explanation:

      Cisterns refers to a system of intercommunicating pools formed by the subarachnoid space at the base of the brain and around the brainstem. Cisterna basalis/basal cistern (interpeduncular cistern) is found at the base of the brain between the two temporal lobes and it contains the arterial circle of Willis. The lumbar cistern is contained in the spinal canal while the foramen magna refers to the opening at the base of the skull though which the spinal cord enters into the skull.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      127.6
      Seconds
  • Question 50 - A biopsy taken from the respiratory passage of a 37 year old male,...

    Correct

    • A biopsy taken from the respiratory passage of a 37 year old male, chronic smoker will mostly likely show which cellular adaptation?

      Your Answer: Stratified squamous metaplasia

      Explanation:

      Metaplasia is a change in the cell type caused in part due to an extrinsic stress on the organ. It involves a change in the surface epithelium from one cell type to the another, most commonly squamous to columnar. This is a reversible process, and removal of the stress should theoretically reverse the surface epithelium back to normal morphology. Respiratory tract metaplasia is a classic example, in which the normal pseudostratified columnar epithelium is replaced by stratified squamous epithelium to better cope with the stress. Under continuous stress metaplasia can progress to dysplasia which is a disordered growth of cells eventually leading to the development of carcinoma.

    • This question is part of the following fields:

      • Cell Injury & Wound Healing; Respiratory
      • Pathology
      35.5
      Seconds
  • Question 51 - An experiment was conducted in which the skeletal muscle protein (not smooth muscle)...

    Correct

    • An experiment was conducted in which the skeletal muscle protein (not smooth muscle) involved in contraction was selectively inhibited. Which protein was inhibited?

      Your Answer: Troponin

      Explanation:

      The mechanism of contraction of smooth muscles is different from that of skeletal muscles in which the contractile protein is troponin whilst in smooth muscle contraction is a protein called calmodulin. Calmodulin reacts with calcium ions and stimulates the formation of myosin crossbridges.

    • This question is part of the following fields:

      • General
      • Physiology
      14.6
      Seconds
  • Question 52 - Biopsy of a neoplastic mass was performed. Histologic examination of the specimen showed...

    Correct

    • Biopsy of a neoplastic mass was performed. Histologic examination of the specimen showed spindle shaped cells with high nuclear/cytoplasm ratio on immunohisto chemical staining. These pleomorphic cells were vimentin positive, cytokeratin negative and cd45 negative. This type of neoplasm is most commonly found in which patient?

      Your Answer: A 15-year-old boy with a mass in the left femur and lung metastases

      Explanation:

      A histology report that describes spindle shaped cells which are vimentin positive suggests osteosarcoma and hematogenous spread to the lungs.

    • This question is part of the following fields:

      • Neoplasia; Orthopaedics
      • Pathology
      18.7
      Seconds
  • Question 53 - Which among the following vertebrae marks the lowest extent of the superior mediastinum?...

    Correct

    • Which among the following vertebrae marks the lowest extent of the superior mediastinum?

      Your Answer: Fourth thoracic

      Explanation:

      The superior mediastinum lies between the manubrium anteriorly and the upper vertebrae of the thorax posteriorly. Below, it is bound by a slightly oblique plane that passes backward from the sternal angle to the lower part of the body of T4 and laterally by the pleura.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      11.9
      Seconds
  • Question 54 - Depression of the normal coagulation system and excessive bleeding after surgery can occur...

    Correct

    • Depression of the normal coagulation system and excessive bleeding after surgery can occur in which of the following medical conditions?

      Your Answer: Liver disease

      Explanation:

      As most of the coagulation factors are synthesized in the liver, liver diseases like hepatitis or cirrhosis will depress the coagulation system. Vitamin K deficiency can also decrease the production of vitamin K dependent coagulation factors VII, XI, X and prothrombin.

    • This question is part of the following fields:

      • General
      • Physiology
      22.5
      Seconds
  • Question 55 - What is the mostly likely cause of prolonged activated partial thromboplastin time (aPPT)...

    Correct

    • What is the mostly likely cause of prolonged activated partial thromboplastin time (aPPT) ?

      Your Answer: Heparin therapy

      Explanation:

      The partial thromboplastin time (PTT) or activated partial thromboplastin time (aPTT) is an indicator for measuring the efficacy of both the intrinsic and common coagulation pathway. Prolonged aPTT may indicate: use of heparin, antiphospholipid antibody and coagulation factor deficiency (e.g., haemophilia). Deficiencies of factors VIII, IX, XI and XII and rarely von Willebrand factor (if causing a low factor VIII level) may lead to a prolonged aPTT correcting on mixing studies.

    • This question is part of the following fields:

      • General
      • Physiology
      6
      Seconds
  • Question 56 - A patient presents with loss of fine touch and sense of proprioception in...

    Correct

    • A patient presents with loss of fine touch and sense of proprioception in the lower part of the body (below T6). He is likely to have a lesion involving:

      Your Answer: Gracile nucleus

      Explanation:

      The gracile nucleus is located in the medulla oblongata and is one of the dorsal column nuclei involved in the sensation of fine touch and proprioception. It contains second-order neurons of the dorsal column–medial lemniscus system, that receive inputs from sensory neurones of the dorsal root ganglia and send axons that synapse in the thalamus.

      The gracile nucleus and fasciculus carry epicritic, kinaesthetic and conscious proprioceptive information from the lower part of the body (below the level of T6 in the spinal cord). Similar information from the upper part of body (above T6, except for face and ear) is carried by the cuneate nucleus and fasciculus. The information from face and ear is carried by the primary sensory trigeminal nucleus.

    • This question is part of the following fields:

      • Neurology
      • Physiology
      7.5
      Seconds
  • Question 57 - Which muscle in the neck divides the neck into two large triangles? ...

    Correct

    • Which muscle in the neck divides the neck into two large triangles?

      Your Answer: Sternocleidomastoid

      Explanation:

      The sternocleidomastoid muscle is an important landmark in the neck as it divides the neck into two; anterior and posterior triangles. These triangles help in the location of the structures of the neck including the carotid artery, head and neck lymph nodes, accessory nerve and the brachial plexus. It originates from the manubrium and medial portion of the clavicle and inserts on the mastoid process of the temporal bone, superior nuchal line. The sternocleidomastoid receives blood supply from the occipital artery and the superior thyroid artery. It is innervated by the accessory nerve (motor) and cervical plexus (sensory).

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      9.8
      Seconds
  • Question 58 - A 30-year-old female was alarmed when she started to experience hair loss and...

    Correct

    • A 30-year-old female was alarmed when she started to experience hair loss and balding, however, she also noted increased hair on her face and body and developed an acne breakout. Deepening of her voice also became prominent. She was referred to an oncologist and was diagnosed with a hormone-producing tumour. What is the most likely diagnosis ?

      Your Answer: Arrhenoblastoma

      Explanation:

      Arrhenoblastoma, known as ‘Sertoli–Leydig tumour’ is a rare ovarian stromal neoplasm that secretes testosterone. It is mostly seen in women in the reproductive years. The key clinical features of this tumour is due to excessive production of testosterone which leads to progressive masculinisation in a woman who was typical normal beforehand. The lesion tends to grow slowly and rarely metastasises. Treatment is surgical removal of the tumour and the prognosis is generally good.

    • This question is part of the following fields:

      • Neoplasia
      • Pathology
      7.5
      Seconds
  • Question 59 - A 13-year-old boy's mother notices he has a lump in his arm, near...

    Correct

    • A 13-year-old boy's mother notices he has a lump in his arm, near his right shoulder. An X-ray reveals a lateral projection in the metaphyseal region of his humerus. The lesion is removed and it is found to be composed of bony cortex, capped by cartilage. What's the most likely diagnosis in this case?

      Your Answer: Osteochondroma

      Explanation:

      Osteochondromas, or osteocartilaginous exostoses, are the most common benign bone tumours, and tend to appear near the ends of long bones. The overgrowth can occur in any bone where cartilage forms bone, and they are capped by cartilage. They are most common in people between the ages of 10-20 years old.

    • This question is part of the following fields:

      • Orthopaedics
      • Pathology
      11.6
      Seconds
  • Question 60 - Which of the following is not seen as a complication of wound healing?...

    Correct

    • Which of the following is not seen as a complication of wound healing?

      Your Answer: Malignancy

      Explanation:

      Complications in wound healing can originate due to abnormalities in the repair process. These abnormalities are :

      1) Deficient scar formation: insufficient granulation tissue can lead to wound dehiscence and ulceration. Dehiscence or wound rupture is seen most commonly in abdominal surgery due to increased intraabdominal pressure. Ulcerations are common in extremity wounds due to inadequate vascularization.

      2) Excessive formation of repair components: collagen being laid down may begin normally however later lead to a raised scar also called a hypertrophic scar, which can extend beyond its boundaries to form a keloid and

      3) Formation of contractures.

    • This question is part of the following fields:

      • Cell Injury & Wound Healing
      • Pathology
      8.7
      Seconds
  • Question 61 - What is the name of the cutaneous branch of the posterior primary ramus...

    Incorrect

    • What is the name of the cutaneous branch of the posterior primary ramus of C2?

      Your Answer: Great auricular nerve

      Correct Answer: Greater occipital nerve

      Explanation:

      The dorsal primary ramus of the spinal nerve C2 is the greater occipital nerve which provides cutaneous innervation to the skin of the back of the head. The ventral primary ramus gives off the great auricular nerve, the lesser occipital nerve and the ansa cervicalis.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      65.1
      Seconds
  • Question 62 - Which of the following is responsible for the activation of pepsinogen released in...

    Incorrect

    • Which of the following is responsible for the activation of pepsinogen released in the stomach?

      Your Answer: Gastrin and pepsin

      Correct Answer: Acid pH and pepsin

      Explanation:

      Pepsinogen is the inactive precursor of pepsin. Once secreted, it comes in contact with hydrochloric acid and pepsin, previously formed, and undergoes cleavage to form active pepsin.

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      7.6
      Seconds
  • Question 63 - Rapid eye movement (REM) sleep is likely to be affected by a lesion...

    Correct

    • Rapid eye movement (REM) sleep is likely to be affected by a lesion in the:

      Your Answer: Pons

      Explanation:

      Rapid eye movement (REM) sleep is also known as paradoxical sleep, as the summed activity of the brain’s neurons is quite similar to that during waking hours. Characterised by rapid movements of the eyes, most of the vividly recalled dreams occur during this stage of sleep. The total time of REM sleep for an adult is about 90–120 min per night.

      Certain neurones in the brainstem, known as REM sleep-on cells, which are located in the pontine tegmentum, are particularly active during REM sleep and are probably responsible for its occurrence. The eye movements associated with REM are generated by the pontine nucleus with projections to the superior colliculus and are associated with PGO (pons, geniculate, occipital) waves.

    • This question is part of the following fields:

      • Neurology
      • Physiology
      4.4
      Seconds
  • Question 64 - An enlarged lymph node which shows well-defined, prominent paracortical follicles with germinal centres...

    Correct

    • An enlarged lymph node which shows well-defined, prominent paracortical follicles with germinal centres is most likely from which of the following patients?

      Your Answer: A 5-year-old boy with a sore throat and runny nose

      Explanation:

      Lymphadenopathy is common in children and is usually reactive in nature. The description fits that of a benign, reactive lymph node.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      6.5
      Seconds
  • Question 65 - Diffusion is the movement of molecules from a region of high concentration to a...

    Correct

    • Diffusion is the movement of molecules from a region of high concentration to a region of low concentration. Which of these changes will decrease the rate of diffusion of a substance?

      Your Answer: An increase in the molecular weight of the substance

      Explanation:

      Unless given IV, a drug must cross several semipermeable cell membranes before it reaches the systemic circulation. Drugs may cross cell membranes by diffusion, amongst other mechanisms. The rate of diffusion of a substance is proportional to the difference in the concentration of the diffusing substance between the two sides of the membrane, the temperature of the solution, the permeability of the membrane and, in the case of ions, the electrical potential difference between the two sides of the membrane.

    • This question is part of the following fields:

      • Fluids & Electrolytes
      • Physiology
      33.3
      Seconds
  • Question 66 - A 31-year-old woman is diagnosed with adrenal hyperplasia, and laboratory samples are taken...

    Correct

    • A 31-year-old woman is diagnosed with adrenal hyperplasia, and laboratory samples are taken to measure serum aldosterone and another substance. Which is most likely to be the other test that was prescribed to this patient?

      Your Answer: Plasma renin

      Explanation:

      The evaluation of a patient in whom hyperaldosteronism is first to determine that hyperaldosteronism is present (serum aldosterone) and, if it is present, to differentiate primary from secondary causes of hyperaldosteronism. The aldosterone-to-renin ratio (ARR) is the most sensitive means of differentiating primary from secondary causes of hyperaldosteronism as it is abnormally increased in primary hyperaldosteronism, and decreased or normal but with high renin levels in secondary hyperaldosteronism.

    • This question is part of the following fields:

      • Physiology
      • Renal
      119.5
      Seconds
  • Question 67 - Which of the following tumours is very radiosensitive? ...

    Incorrect

    • Which of the following tumours is very radiosensitive?

      Your Answer: Chondrosarcoma

      Correct Answer: Seminoma

      Explanation:

      Seminoma is the most radiosensitive tumour and responds well to radiation therapy after unilateral orchidectomy. The ipsilateral inguinal areas are routinely not treated however, depending on the stage, the mediastinum and the left supraclavicular regions may also be irradiated.

    • This question is part of the following fields:

      • Neoplasia; Urology
      • Pathology
      9.9
      Seconds
  • Question 68 - Which of the following structures carry part of the right bundle branch of...

    Correct

    • Which of the following structures carry part of the right bundle branch of the AV bundle?

      Your Answer: Moderator band (septomarginal trabecula)

      Explanation:

      The moderator band extends from the base of the anterior papillary muscle to the ventricular septum. It is the structure which carries part of the right AV bundle. Its role it to prevent overdistention of the ventricle.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      6.1
      Seconds
  • Question 69 - Which of the following will be affected by a lesion in the posterior...

    Correct

    • Which of the following will be affected by a lesion in the posterior column-medial lemniscus system?

      Your Answer: Fine touch

      Explanation:

      The posterior column–medial lemniscus (PCML) pathway is a sensory pathway that transmits fine touch and conscious proprioceptive information from the body to the brain. As the posterior columns are also known as dorsal columns, the pathway is also called the dorsal column–medial lemniscus system or DCML.

    • This question is part of the following fields:

      • Neurology
      • Physiology
      18.6
      Seconds
  • Question 70 - Severe abdominal pain radiating to the back, along with increased serum amylase levels,...

    Correct

    • Severe abdominal pain radiating to the back, along with increased serum amylase levels, is seen in which of the following conditions?

      Your Answer: Pancreatitis

      Explanation:

      The primary test for diagnosis and monitoring of pancreatitis is amylase. Increased plasma levels of amylase can be found in: salivary trauma (including anaesthetic intubation), mumps, pancreatitis and renal failure. However, a rise in the total amylase levels over 10 times the upper limit of normal (ULN) is suggestive of pancreatitis; 5–10 times the ULN may indicate ileus or duodenal disease or renal failure. Lower levels are commonly found in salivary gland disease.

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      7.4
      Seconds
  • Question 71 - Inside the palatoglossal arch is a muscle. Which nerve innervates this muscle? ...

    Incorrect

    • Inside the palatoglossal arch is a muscle. Which nerve innervates this muscle?

      Your Answer: IX

      Correct 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

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      9.6
      Seconds
  • Question 72 - A surgeon performing a Whipple's procedure, that involves mobilizing the head of the...

    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 pancrease which bled out. Which structure is most likely to have been injured?

      Your Answer: Superior mesenteric artery

      Explanation:

      The structure immediately posterior to the neck of the pancreas is the superior mesenteric vein. The neck of the pancreas lies anterior to the superior mesenteric vein, which joins with the splenic vein to form the portal vein.

      The superior mesenteric artery (SMA) is also located in proximity to the neck of the pancreas. Specifically, the SMA emerges from the abdominal aorta just below the level of the pancreas and passes posterior to the neck of the pancreas before it descends into the mesentery to supply the intestines. Thus, both the superior mesenteric vein and the superior mesenteric artery are key vascular structures related to the posterior aspect of the neck of the pancreas.

      Bleeding out would suggest an arterial injury.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      13.8
      Seconds
  • Question 73 - Pain in the right upper quadrant of the abdomen on ingestion of a...

    Correct

    • 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.

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      13.5
      Seconds
  • Question 74 - A 34-year-old man is receiving chemotherapy for non-Hodgkin's lymphoma. Which of the following...

    Correct

    • A 34-year-old man is receiving chemotherapy for non-Hodgkin's lymphoma. Which of the following chemotherapy regimens would be used in this case?

      Your Answer: CHOP

      Explanation:

      CHOP is the acronym for a chemotherapy regimen used in the treatment of non-Hodgkin’s lymphoma, comprising cyclophosphamide, hydroxyrubicin (adriamycin), vincristine and prednisone. This regimen can also be combined with the monoclonal antibody rituximab if the lymphoma is of B cell origin; this combination is called R-CHOP.

    • This question is part of the following fields:

      • Pathology
      • Pharmacology
      6.4
      Seconds
  • Question 75 - What is the role of ICAM-1 and VCAM-1 in the inflammatory process? ...

    Correct

    • What is the role of ICAM-1 and VCAM-1 in the inflammatory process?

      Your Answer: Leukocyte adhesion

      Explanation:

      Steps involved in leukocyte arrival and function include:

      1. margination: cells migrate 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. Interaction of these results in adhesion.

      4. diapedesis and chemotaxis: diapedesis is the transmigration of the leukocyte across the endothelium of the capillary and towards a chemotactic product.

      5. phagocytosis: engulfing the offending substance/cell.

    • This question is part of the following fields:

      • Inflammation & Immunology
      • Pathology
      3.2
      Seconds
  • Question 76 - Identify which of the following muscles acts on two joints? ...

    Correct

    • Identify which of the following muscles acts on two joints?

      Your Answer: Sartorius

      Explanation:

      The sartorius muscle, the longest muscle in the body, is one of the two jointed or biarticular muscles. It originates from the anterior superior iliac spine and part of the notch between the anterior superior iliac spine and anterior inferior iliac spine and crosses both the hip joint and the knee joint. At the hip joint the sartorius flexes and rotates the thigh at the hip joint and flexes the leg at the knee joint.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      2.9
      Seconds
  • Question 77 - Which of the following clinical signs will be demonstrated in a case of...

    Correct

    • Which of the following clinical signs will be demonstrated in a case of Brown-Séquard syndrome due to hemisection of the spinal cord at mid-thoracic level?

      Your Answer: Ipsilateral spastic paralysis, ipsilateral loss of vibration and proprioception (position sense) and contralateral loss of pain and temperature sensation beginning one or two segments below the lesion

      Explanation:

      Brown–Séquard syndrome results due to lateral hemisection of the spinal cord and results in a loss of motricity (paralysis and ataxia) and sensation. The hemisection of the cord results in a lesion of each of the three main neural systems: the principal upper motor neurone pathway of the corticospinal tract, one or both dorsal columns and the spinothalamic tract. As a result of the injury to these three main brain pathways the patient will present with three lesions. The corticospinal lesion produces spastic paralysis on the same side of the body (the loss of moderation by the upper motor neurons). The lesion to fasciculus gracilis or fasciculus cuneatus results in ipsilateral loss of vibration and proprioception (position sense). The loss of the spinothalamic tract leads to pain and temperature sensation being lost from the contralateral side beginning one or two segments below the lesion. At the lesion site, all sensory modalities are lost on the same side, and an ipsilateral flaccid paralysis.

    • This question is part of the following fields:

      • Neurology
      • Physiology
      18.4
      Seconds
  • Question 78 - A pedestrian sustained a left fibula fractured following a hit-and-run. X-rays showed that...

    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.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      9.9
      Seconds
  • Question 79 - Which muscles are attached to the tibial tuberosity? ...

    Correct

    • Which muscles are attached to the tibial tuberosity?

      Your 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).

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      3.6
      Seconds
  • Question 80 - Which type of contractions are responsible for the propulsion of chyme along the...

    Correct

    • Which type of contractions are responsible for the propulsion of chyme along the small intestine?

      Your Answer: Segmentation

      Explanation:

      Two major types of intestinal contractions are segmentation and peristalsis:

      Segmentation occurs most frequently and primarily involves circular muscle. It is essentially a contraction of 2- or 3-cm long intestinal segments while the muscle on either side of it relaxes. Chyme in the segment is displaced in both directions. As the contracted segment relaxes, the previously relaxed segments on either side may contract. This efficiently mixes the chyme with the digestive secretions and exposes the mucosal absorptive surface to the luminal contents. It also serves a propulsive function and contributes to the movement of chyme.

      Peristalsis is a propulsive wave of contraction that is initiated by intestinal distension. It is short lived and travels only a few centimetres before dying out. The combined effects of intestinal peristalsis and segmentation provide for both adequate mixing of the intestinal contents and slow, steady movement of chyme.

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      3.8
      Seconds
  • Question 81 - A 40 year old man from Japan was diagnosed with cancer of the...

    Correct

    • A 40 year old man from Japan was diagnosed with cancer of the oesophagus. He is to undergo esophagectomy. While mobilizing the oesophagus in the neck, for resection and anastomosis with the stomach tube on the left side, the surgeon must be cautious not to injure a vital structure. Which of the following is it?

      Your Answer: Thoracic duct

      Explanation:

      The oesophagus is divided into 3 portions: cervical (part that is in the neck), thoracic portion and the abdominal portion. The cervical part is bordered by the trachea anteriorly and the prevertebral fascia covering the bodies of the 6,7 and 8th vertebra posteriorly. The thoracic duct lies on the left side at the level of the sixth cervical vertebra. The carotid sheath with its contents and lower poles of the lateral lobes of thyroid gland are lateral. The thoracic duct is the structure most likely to be injured.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      17.7
      Seconds
  • Question 82 - Which of the following abnormalities can be seen in patients with hypermagnesemia? ...

    Correct

    • Which of the following abnormalities can be seen in patients with hypermagnesemia?

      Your Answer: Respiratory depression

      Explanation:

      Hypermagnesemia is an electrolyte disturbance in which there is a high level of magnesium in the blood. It is defined as a level greater than 1.1 mmol/L. Symptoms include weakness, confusion, decreased breathing rate, and cardiac arrest.

    • This question is part of the following fields:

      • Fluids & Electrolytes
      • Pathology
      4.6
      Seconds
  • Question 83 - A patient with this condition has extracellular fluid volume expansion: ...

    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.

    • This question is part of the following fields:

      • Fluids & Electrolytes
      • Pathology
      13.7
      Seconds
  • Question 84 - What principal artery that supplies the meninges is susceptible to rupture following trauma...

    Correct

    • What principal artery that supplies the meninges is susceptible to rupture following trauma to the side of the head over the temporal region:

      Your Answer: Middle meningeal artery

      Explanation:

      The middle meningeal artery normally arises from the first or mandibular segment of the maxillary artery. The artery runs in a groove on the inside of the cranium, this can clearly be seen on a lateral skull X-ray. An injured middle meningeal artery is the most common cause of an epidural hematoma.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      4
      Seconds
  • Question 85 - Which of the following morphological characteristic is a salient feature of a pure...

    Correct

    • Which of the following morphological characteristic is a salient feature of a pure apoptotic cell?

      Your 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.

    • This question is part of the following fields:

      • Cell Injury & Wound Healing
      • Pathology
      8.5
      Seconds
  • Question 86 - A 55-years-old man presented to the emergency department complaining of a squeezing sensation...

    Correct

    • A 55-years-old man presented to the emergency department complaining of a squeezing sensation in his chest that has spread to his neck with associated worsening shortness of breath. Which of these laboratory tests would you ask for in this patient:

      Your Answer: Creatine kinase-MB

      Explanation:

      Creatine kinase-MB is a test that usually is ordered when the patient has chest pain as a cardiac marker. When a heart attack is suspected and a troponin test (which is more specific for heart damage), is not available CK-MB is ordered. There are 3 forms of CK: CK-MM, CK-BB and CK-MB. CK-MB is commonly found in heart tissue, therefore injured heart muscle cells release CK-MB into the blood. Elevated CK-MB levels indicate that it is probable that a person has recently had a heart attack.

    • This question is part of the following fields:

      • Cardiovascular
      • Pathology
      8.9
      Seconds
  • Question 87 - Which of the following structures is not easily palpable? ...

    Correct

    • Which of the following structures is not easily palpable?

      Your Answer: Styloid process of the temporal bone

      Explanation:

      The styloid process is a thin, pointed process that projects antero-inferiorly from the base of the petrous temporal bone. It can vary in length from a short, stubby process to a slender, four to five centimetre rod. It forms from the cranial elements of the second pharyngeal arch. The tympanic plate of the temporal bone ensheathes the base of this process. The pointed, projecting portion of the process provides attachment to the stylohyoid and stylomandibular ligaments, and to three muscles – the styloglossus, stylohyoid, and stylopharyngeus. As the styloid process is covered by the various muscles, it is not easily palpable in live subjects.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      4.9
      Seconds
  • Question 88 - A teacher had varicosities in the region of the small saphenous vein. Which...

    Correct

    • A teacher had varicosities in the region of the small saphenous vein. Which of the following is true about that vein?

      Your Answer: Has nine to twelve valves

      Explanation:

      It is known that the small saphenous vein has nine to twelve valves along its course. This vein begins as a direct continuation of the lateral marginal vein posterior to the lateral malleolus. It is superficially situated but closer to its termination, perforates the deep fascia in the lower part of the popliteal fossa to end in the popliteal vein.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      6.4
      Seconds
  • Question 89 - When at rest, which of the following will be higher in a marathon...

    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.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      4.1
      Seconds
  • Question 90 - A computer tomography guided needle biopsy is done on a patient with a...

    Correct

    • A computer tomography guided needle biopsy is done on a patient with a cystic swelling in the left chest. The radiologist inserted the biopsy needle into the 9th intercostal space along the mid axillary line to aspirate the swelling and obtain tissue for histological diagnosis. In which space is the swelling most likely to be?

      Your Answer: Costodiaphragmatic recess

      Explanation:

      The costodiaphragmatic recess is the lowest point of the pleural sac where the costal pleura becomes the diaphragmatic pleura. At the midclavicular line, this is found between ribs 6 and 8; at the paravertebral lines, between ribs 10 and 12 and between ribs 8 and 10 at the midaxillary line.

      The cardiac notch: is an indentation of the heart on the left lung, located on the anterior surface of the lung.

      Cupola: part of the parietal pleura that extends above the first rib.

      Oblique pericardial sinus: part of the pericardial sac located posterior to the heart behind the left atrium.

      Costomediastinal recess: a reflection of the pleura from the costal surface to the mediastinal surface, is on the anterior surface of the chest.

      The inferior mediastinum: is the space in the chest occupied by the heart.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      7.1
      Seconds
  • Question 91 - Which of the following is NOT true regarding malignant hyperpyrexia ...

    Correct

    • Which of the following is NOT true regarding malignant hyperpyrexia

      Your 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.

    • This question is part of the following fields:

      • Pathology
      • Pharmacology
      7.7
      Seconds
  • Question 92 - What is the innervation of the tensor tympani muscle? ...

    Incorrect

    • What is the innervation of the tensor tympani muscle?

      Your Answer: Facial nerve

      Correct Answer: Trigeminal nerve

      Explanation:

      The tensor veli palatini is innervated by the medial pterygoid nerve, a branch of mandibular nerve, the third branch of the trigeminal nerve (CN V3) – the only muscle of the palate not innervated by the pharyngeal plexus, which is formed by the vagal and glossopharyngeal nerves.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      12.6
      Seconds
  • Question 93 - A sudden loud sound is more likely to result in cochlear damage than...

    Correct

    • A sudden loud sound is more likely to result in cochlear damage than a slowly developing loud sound. This is because:

      Your Answer: There is a latent period before the attenuation reflex can occur

      Explanation:

      On transmission of a loud sound into the central nervous system, an attenuation reflex occurs after a latent period of 40-80 ms. This reflex contracts the two muscles that pull malleus and stapes closer, developing a high degree of rigidity in the entire ossicular chain. This reduces the ossicular conduction of low frequency sounds to the cochlea by 30-40 decibels. In this way, the cochlea is protected from damage due to loud sounds (these are low frequency sounds) when they develop slowly.

    • This question is part of the following fields:

      • Neurology
      • Physiology
      13.6
      Seconds
  • Question 94 - The superior pancreaticoduodenal artery, the artery that supplies blood to the pancreas and...

    Incorrect

    • The superior pancreaticoduodenal artery, the artery that supplies blood to the pancreas and the duodenum, is a branch of the:

      Your Answer: Superior mesenteric artery

      Correct 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.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      9
      Seconds
  • Question 95 - A man was stabbed in the thigh following a bar brawl. A superficial...

    Correct

    • A man was stabbed in the thigh following a bar brawl. A superficial vein was injured which terminates in the femoral vein. This superficial vein is?

      Your Answer: Great saphenous

      Explanation:

      The great saphenous vein is considered the longest vein in the body. It terminates in the femoral vein nearly 3cm below the inguinal ligament. It begins at the dorsum of the foot in the medial marginal vein and ascends at the medial side of the leg in relation with the saphenous nerve.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      10.6
      Seconds
  • Question 96 - A 24 year old mother is breastfeeding her first child. Which of the...

    Correct

    • A 24 year old mother is breastfeeding her first child. Which of the following cellular adaptations occurred in her breast tissue to allow her to do this?

      Your Answer: Lobular hyperplasia

      Explanation:

      Under the influence of oestrogen in pregnancy, there is an increase in the number of lobules which will facilitate lactation.

      Steatocytes occur due to loss of weight and nutritional deficit.

      Metaplasia is a normal physiological process which is due to a change in normal epithelium with another type.

      Lobular atrophy will result in a decreased capacity to provide milk.

    • This question is part of the following fields:

      • Cell Injury & Wound Healing; Female Health
      • Pathology
      5.8
      Seconds
  • Question 97 - A 7-year-old boy with facial oedema was brought to the hospital by his...

    Correct

    • A 7-year-old boy with facial oedema was brought to the hospital by his parents. Renal function is normal and urinalysis revealed the presence of a profound proteinuria. Which of the following is the most probable cause of these findings?

      Your Answer: Minimal-change disease

      Explanation:

      Minimal-change disease (MCD) refers to a histopathologic glomerular lesion, typically found in children, that is almost always associated with nephrotic syndrome. The most noticeable symptom of MCD is oedema, which can develop very rapidly. Due to the renal loss of proteins muscle wasting and growth failure may be seen in children. Renal function is usually not affected and a proteinuria of more than 40 mg/h/m2 is the only abnormal finding in urinalysis.

    • This question is part of the following fields:

      • Pathology
      • Renal
      9.1
      Seconds
  • Question 98 - The circle of Willis is one of the cerebrovascular safeguards comprised of the...

    Correct

    • The circle of Willis is one of the cerebrovascular safeguards comprised of the left and the right posterior communicating artery. Which of the following arteries in the brain is connected to the posterior cerebral artery by these posterior communicating arteries?

      Your Answer: Internal carotid artery

      Explanation:

      The Circle of Willis is an anastomosis of cerebral arteries that are located at the base of the brain. The Circle of Willis is one of the important safeguards that ensure back up of blood supply to parts of the brain in case of any cerebrovascular accident. The Circle of Willis is made up of an anterior portion of arteries including; the anterior cerebral arteries. The anterior cerebral arteries are connected to the posterior portion of the circle of Willis by the anterior communicating artery. The posterior portion is made up of the posterior cerebral artery which branch off from the basilar artery. The posterior cerebral artery are connected to the anterior portion of the circle of Willis by the posterior communicating artery. The posterior communicating artery connects the posterior cerebral artery to the internal carotid artery. The circle of Willis receives blood supply from the left and right internal carotid arteries that continues as the middle cerebral artery and posteriorly from the two vertebral arteries that join to form the basilar artery.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      8.9
      Seconds
  • Question 99 - A blood sample from a patient with polycythaemia vera will show which of...

    Correct

    • A blood sample from a patient with polycythaemia vera will show which of the following abnormalities?

      Your Answer: High platelet count

      Explanation:

      Polycythaemia is a condition that results in an increase in the total number of red blood cells (RBCs) in the blood. It can be due to a myeloproliferative syndrome, chronically low oxygen levels or rarely malignancy. In primary polycythaemia/ polycythaemia vera the increase is due to an abnormality in the bone marrow, resulting in increased RBCs, white blood cells (WBCs) and platelets. In secondary polycythaemia the increase occurs due to high levels of erythropoietin either artificially or naturally. The increase is about 6-8 million/cm3 of blood. A type of secondary polycythaemia is physiological polycythaemia where people living in high altitudes who are exposed to hypoxic conditions produce more erythropoietin as a compensatory mechanism for thin oxygen and low oxygen partial pressure.

    • This question is part of the following fields:

      • General
      • Physiology
      3.9
      Seconds
  • Question 100 - A 27-year-old HIV patient started on an antifungal agent. Which antifungal agent that...

    Correct

    • A 27-year-old HIV patient started on an antifungal agent. Which antifungal agent that inhibits the biosynthesis of fungal ergosterol was given to the patient?

      Your Answer: Ketoconazole

      Explanation:

      Ketoconazole is a synthetic imidazole antifungal drug used primarily to treat fungal infections. It inhibits the biosynthesis of ergosterol by blocking demethylation at the C14 site of the ergosterol precursor. Amphotericin B and Nystatin impair permeability of the cell membrane. Flucytosine interferes with DNA synthesis, while the target of griseofulvin is the microtubules

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      5.4
      Seconds
  • Question 101 - A 20 year lady is brought to the A&E following a road accident....

    Correct

    • A 20 year lady is brought to the A&E following a road accident. She is hypotensive and a CT scan of the abdomen reveals a shattered spleen. An emergency splenectomy is performed where the splenic artery is ligated right at its origin. Which of the following arteries will have a diminished blood flow owing to ligation of the splenic artery at its origin?

      Your Answer: Left gastroepiploic

      Explanation:

      Ligation of the splenic artery right at its point of origin should cut off blood flow in its branches. The following are the branches of the splenic artery: pancreatic branches, short gastric branches and left gastroepiploic arteries.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      18.8
      Seconds
  • Question 102 - Which of the following diseases causes abrupt vertigo, nausea, vomiting, tinnitus, and nystagmus?...

    Correct

    • Which of the following diseases causes abrupt vertigo, nausea, vomiting, tinnitus, and nystagmus?

      Your Answer: Vestibular neuronitis

      Explanation:

      Vestibular neuronitis or labyrinthitis causes a self-limited episode of vertigo, presumably due to inflammation of the vestibular division of cranial nerve VIII. Its causes are unknown, It may be due to a virus, but it can be related to a bacterial infection, head injury, stress, allergy, or as a reaction to medication. Symptoms can last up to 7-10 days.

    • This question is part of the following fields:

      • Neurology
      • Pathology
      12.9
      Seconds
  • Question 103 - A 40-year old woman presents with tightening of the skin over her fingers...

    Correct

    • A 40-year old woman presents with tightening of the skin over her fingers which makes movement of her fingers difficult.. She also gives a history of her fingers turning blue on exposure to low temperatures. She admits to gradual weight loss. Investigations reveal negative rheumatoid factor, negative antinuclear antibody and a positive anticentromere body. Which of the following conditions is she likely to have?

      Your Answer: Oesophageal stricture

      Explanation:

      Scleroderma is a connective tissue disorder that ranges in severity and progression. The disease could show generalised skin thickening with rapid, fatal, visceral involvement; or only cutaneous involvement (typically fingers and face). The slow progressive form is also known as ‘limited cutaneous scleroderma’ or CREST syndrome (calcinosis cutis, Raynaud’s phenomenon, (o)oesophageal dysmotility, sclerodactyly, and telangiectasia).

    • This question is part of the following fields:

      • Gastrointestinal; Hepatobiliary
      • Pathology
      12.1
      Seconds
  • Question 104 - The dilator pupillae muscle is innervated by postganglionic sympathetic fibres. Where do the...

    Incorrect

    • The dilator pupillae muscle is innervated by postganglionic sympathetic fibres. Where do the postganglionic sympathetic fibres originate?

      Your Answer: Ciliary ganglion

      Correct Answer: Superior cervical ganglion

      Explanation:

      The postganglionic sympathetic axons are derived from the superior cervical ganglion and innervate the eye and lacrimal gland allowing for vasoconstriction of the iris and sclera, pupillary dilation, widening of the palpebral fissure, and a reduction in tear production.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      7.3
      Seconds
  • Question 105 - A 70 year old women, died suddenly. She had a history of hypertension...

    Correct

    • A 70 year old women, died suddenly. She had a history of hypertension and aortic stenosis. On autopsy her heart weighed 550g. What is the most likely cause of this pathology?

      Your Answer: Hypertrophy

      Explanation:

      Due to increased pressure on the heart as a result of hypertension and aortic stenosis, the myocardial fibres hypertrophied to adapt to the increased pressure and to effectively circulate blood around the body. Hyperplasia could not occur, as myocardial fibres are stable cells and cannot divide further.

      Fat does not deposit in the heart due to volume overload.

      Myocardial oedema is not characteristic of a myocardial injury.

      Metaplasia is a change in the type of epithelium.

      Atrophy would result in a decreased heart size and inability to function.

    • This question is part of the following fields:

      • Cell Injury & Wound Healing; Cardiovascular
      • Pathology
      5.1
      Seconds
  • Question 106 - A patient is diagnosed with a tumour of the parotid gland. During surgical...

    Correct

    • A patient is diagnosed with a tumour of the parotid gland. During surgical removal of the gland, which artery is vulnerable to injury?

      Your Answer: External carotid artery

      Explanation:

      The external carotid artery is a major artery of the head and neck. It arises from the common carotid artery when it splits into the external and internal carotid artery. It supplies blood to the face and neck. The external carotid artery begins opposite the upper border of the thyroid cartilage and, taking a slightly curved course, passes upward and forward and then inclines backward to the space behind the neck of the mandible, where it divides into the superficial temporal and internal maxillary arteries. It rapidly diminishes in size in its course up the neck, owing to the number and large size of the branches given off from it. At its origin, this artery is more superficial and placed nearer the midline than the internal carotid and is contained within the carotid triangle. The external carotid artery is covered by the skin, superficial fascia, platysma, deep fascia and anterior margin of the sternocleidomastoid. It is crossed by the hypoglossal nerve, by the lingual, ranine, common facial and superior thyroid veins; and by the digastric and stylohyoid; higher up it passes deeply into the substance of the parotid gland, where it lies deep to the facial nerve and the junction of the temporal and internal maxillary veins. It is here that it is in danger during surgery of the parotid gland.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      17.2
      Seconds
  • Question 107 - Injury to this nerve will affect the function of the palatoglossus and levator...

    Incorrect

    • Injury to this nerve will affect the function of the palatoglossus and levator veli palatini muscles:

      Your Answer: Cranial nerve XII

      Correct Answer: Cranial nerve X

      Explanation:

      The vagus nerve (cranial nerve X) innervates both the palatoglossus and levator veli palatini muscles.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      12.8
      Seconds
  • Question 108 - In the glomerulus of the kidney, the mesangium is a structure associated with the capillaries. It has extraglomerular mesangial...

    Correct

    • 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.

    • This question is part of the following fields:

      • Physiology
      • Renal
      10.6
      Seconds
  • Question 109 - Which statement is true regarding the diaphragmatic openings: ...

    Incorrect

    • Which statement is true regarding the diaphragmatic openings:

      Your Answer: The left phrenic nerve passes through the opening at T8

      Correct Answer: The thoracic duct passes through the opening at T12

      Explanation:

      The diaphragmatic openings are:

      T8 – opening for the inferior vena cavaand the right phrenic nerve

      T10 – opening for the oesophagusand the left gastric artery and vein

      T12 – opening for the aorta, the thoracic duct and azygos vein.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      41.6
      Seconds
  • Question 110 - A patient sustained an iatrogenic injury to one of the structures passing through...

    Incorrect

    • A patient sustained an iatrogenic injury to one of the structures passing through the deep inguinal ring. This was during an operation to repair an inguinal hernia. Which structure is most likely to be injured?

      Your Answer: Ilioinguinal nerve

      Correct Answer: Round ligament of the uterus

      Explanation:

      The deep inguinal ring transmits the spermatic cord in the man and the round ligament of the uterus in the female. It is bound below and medially by the inferior epigastric vessels (so these don’t go through it).

      The ilioinguinal nerve, although it courses through the inguinal canal, does not pass through it.

      The iliohypogastric nerves run between the internal oblique and transversus abdominis in the abdominal wall, piercing the internal oblique at the anterior superior iliac spine to travel just deep to the external oblique.

      The inferior epigastric artery runs between the transversus abdominis and the peritoneum forming the lateral umbilical fold.

      The medial umbilical ligament is the obliterated umbilical artery that it lies within the medial umbilical fold of peritoneum.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      14.3
      Seconds
  • Question 111 - Regarding the long head of the biceps femoris, which of the following is...

    Correct

    • Regarding the long head of the biceps femoris, which of the following is correct?

      Your Answer: It crosses two joints

      Explanation:

      The long head of the biceps femoris arises from the lower and inner impression on the back of the tuberosity of the ischium. It inserts with the short head in an aponeurosis which becomes a tendon and this tendon is inserted into the lateral side of the head of the fibula and the lateral condyle of the tibia, thus crossing two joints.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      60.3
      Seconds
  • Question 112 - A 12-year old girl was brought to the hospital with recurrent headaches for...

    Correct

    • A 12-year old girl was brought to the hospital with recurrent headaches for 6 months. Her physical examination revealed no abnormality. A CT scan of the head revealed a suprasellar mass with calcifications, eroding the surrounding sella turcica. The lesion is likely to represent:

      Your Answer: Craniopharyngioma

      Explanation:

      Craniopharyngiomas (also known as Rathke pouch tumours, adamantinomas or hypophyseal duct tumours) affect children mainly between the age of 5 and 10 years. It constitutes 9% of brain tumours affecting the paediatric population. These are slow-growing tumours which can also be cystic, and arise from the pituitary stalk, specifically the nests of epithelium derived from Rathke’s pouch. Histologically, this tumour shows nests of squamous epithelium which is lined on the outside by radially arranged cells. Calcium deposition is often seen with a papillary type of architecture.

      ACTH-secreting pituitary adenomas are rare and mostly microadenomas. Paediatric astrocytoma’s usually occur in the posterior fossa. Although null cell adenomas can cause mass effect and give rise to the described symptoms, they are not suprasellar. Prolactinomas can also show symptoms of headache and disturbances in the visual field, however they are known to be small and slow-growing.

    • This question is part of the following fields:

      • Endocrine
      • Pathology
      21
      Seconds
  • Question 113 - A 16-year old boy was brought in an unconscious state to the emergency...

    Correct

    • A 16-year old boy was brought in an unconscious state to the emergency department. Clinical evaluation pointed in favour of acute adrenal insufficiency. On enquiry, it was revealed that he was suffering from a high grade fever 24 hours prior. On examination, extensive purpura were noted on his skin. The likely diagnosis is:

      Your Answer: Meningococcaemia

      Explanation:

      Findings described are suggestive of Waterhouse-Friderichsen syndrome which develops secondary to meningococcaemia. The reported incidence of Addison’s disease is 4 in 100,000. It affects both sexes equally and is seen in all age groups. It tends to show clinical symptoms at the time of metabolic stress or trauma. The symptoms are precipitated by acute infections, trauma, surgery or sodium loss due to excessive perspiration.

    • This question is part of the following fields:

      • Endocrine
      • Pathology
      11.9
      Seconds
  • Question 114 - A 34-year-old Asian male presents with cervical lymphadenopathy. The patient is suspected to...

    Correct

    • A 34-year-old Asian male presents with cervical lymphadenopathy. The patient is suspected to have tuberculous lymphadenopathy. Excision biopsy of one of the nodes showed granulomatous inflammation. Which histopathologic feature is most likely consistent with the diagnosis of tuberculosis?

      Your Answer: Caseation necrosis

      Explanation:

      The granulomas of tuberculosis tend to contain necrosis (caseating tubercles), but non-necrotizing granulomas may also be present. Multinucleated giant cells with nuclei arranged like a horseshoe (Langhans giant cells) and foreign body giant cells are often present, but are not specific for tuberculosis. A definitive diagnosis of tuberculosis requires identification of the causative organism by microbiological cultures.

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      109.2
      Seconds
  • Question 115 - Which of these substances is secreted by pericytes in the juxtaglomerular cells? ...

    Correct

    • Which of these substances is secreted by pericytes in the juxtaglomerular cells?

      Your Answer: Renin

      Explanation:

      The juxtaglomerular cells synthesise, store and secrete the enzyme renin in the kidney. They are specialised smooth muscle cells in the wall of the afferent arteriole that delivers blood to the glomerulus and thus play a critical role in the renin– angiotensin system and so in renal autoregulation.

    • This question is part of the following fields:

      • Physiology
      • Renal
      20.5
      Seconds
  • Question 116 - The gradual depolarization in-between action potentials in pacemaker tissue is a result of?...

    Correct

    • The gradual depolarization in-between action potentials in pacemaker tissue is a result of?

      Your Answer: A combination of gradual inactivation outward IK along with the presence of an inward ‘funny’ current (If) due to opening of channels permeable to both Na+ and K+ ions

      Explanation:

      One of the characteristic features of the pacemaker cell is the generation of a gradual diastolic depolarization also called the pacemaker potential. In phase 0, the upstroke of the action potential caused by an increase in the Ca2+ conductance, an influx of calcium occurs and a positive membrane potential is generated. The next is phase 3 which is repolarization caused by increased K+ conductance as a result of outwards K+ current. Phase 4 is a slow depolarization which accounts for the pacemaker activity, caused by increased conductance of Na+, inwards Na+ current called IF. it is turned on by repolarization.

    • This question is part of the following fields:

      • General
      • Physiology
      46.6
      Seconds
  • Question 117 - The superior ulnar collateral artery is a direct branch of this artery: ...

    Correct

    • The superior ulnar collateral artery is a direct branch of this artery:

      Your 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.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      50.5
      Seconds
  • Question 118 - A tumour on the floor of the fourth ventricle is most likely to...

    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.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      8.8
      Seconds
  • Question 119 - A woman that presented with dyspnoea, chest pain and cough was found to...

    Correct

    • A woman that presented with dyspnoea, chest pain and cough was found to have a serous pleural effusion. This finding is most likely to be associated with which of the following conditions?

      Your Answer: Congestive heart failure

      Explanation:

      A pleural effusion is defined as an abnormal collection of fluid in the pleural space. Pleural effusion can result from excess fluid production or decreased absorption or both. Thoracentesis and laboratory testing help determine the origin of the accumulated fluid. Serous fluid accumulation in the pleural space indicates the presence of a hydrothorax and is most likely to develop secondary to congestive heart failure.

    • This question is part of the following fields:

      • Pathology
      • Respiratory
      22
      Seconds
  • Question 120 - A young women following a road traffic accident suffered heavy blood loss and...

    Correct

    • A young women following a road traffic accident suffered heavy blood loss and developed subsequent anaemia. Which of the following is a consequence of this?

      Your Answer: A high reticulocyte count

      Explanation:

      Anaemia refers to a decrease in the circulating levels of haemoglobin in the blood resulting in a reduced ability of the body to transport oxygen effectively. Anaemia from blood loss results in the body further compensating by releasing stored RBCs and immature RBCs from the bone marrow. Thus resulting in a high reticulocyte count.

    • This question is part of the following fields:

      • General
      • Physiology
      78.5
      Seconds
  • Question 121 - The LEAST mobile structure in the peritoneal cavity is the: ...

    Correct

    • The LEAST mobile structure in the peritoneal cavity is the:

      Your Answer: Pancreas

      Explanation:

      The presence or absence of the mesentery determines mobility of abdominal contents. Structures like the stomach, transverse colon and appendix have mesenteries and thus are relatively mobile. In contrast, the pancreas is a retroperitoneal (behind the peritoneum) structure and therefore is fixed. The greater omentum is a large mobile fold of omentum that hangs down from the stomach .

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      38.8
      Seconds
  • Question 122 - Which of the following is a landmark to identify the site of the...

    Correct

    • Which of the following is a landmark to identify the site of the 2nd costal cartilage?

      Your Answer: Sternal angle

      Explanation:

      The sternal angle is an important part where the second costal cartilage attaches to the sternum. Finding the sternal angle will help in finding the second costal cartilage and intercostal space.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      31.4
      Seconds
  • Question 123 - A 40-year old gentleman, known with a history of peptic ulcer disease, was...

    Correct

    • A 40-year old gentleman, known with a history of peptic ulcer disease, was brought to the clinic in a dehydrated state with persistent vomiting. His blood investigations revealed:
      • sodium = 142 mmol/l
      • potassium = 2.6 mmol/l
      • chloride = 85 mmol/l
      • pH = 7.55
      • p(CO2) = 50 mmHg
      • p(O2) = 107 mmHg
      • standard bicarbonate = 40 mmol/l
      This patient has a:

      Your Answer: Metabolic alkalosis

      Explanation:

      High pH with high standard bicarbonate indicates metabolic alkalosis. The pa(CO2) was appropriately low in compensation. This is hypokalaemic hypochloraemic metabolic acidosis due to prolonged vomiting. Treatment includes treating the cause and intravenous sodium chloride with potassium.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      38.8
      Seconds
  • Question 124 - Gram positive bacteria differ from gram negative bacteria due to the presence of...

    Correct

    • Gram positive bacteria differ from gram negative bacteria due to the presence of which of the following structures?

      Your Answer: Outer membrane

      Explanation:

      The reason bacteria are either Gram-positive or Gram-negative is due to the structure of their cell envelope (the cell envelope is defined as the cell membrane and cell wall plus an outer membrane, if one is present.) Gram-positive bacteria, for example, retain the crystal violet due to the amount of peptidoglycan in the cell wall. It can be said therefore that the Gram-stain procedure separates bacteria into two broad categories based on structural differences in the cell envelope.

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      5
      Seconds
  • Question 125 - Whipple's procedure involves mobilizing the head of the pancreas. As the surgeon does...

    Correct

    • Whipple's procedure involves mobilizing the head of the pancreas. As the surgeon does this, he must be careful to avoid injury to a key structure that is found lying behind the head of the pancreas. Which vital structure is this?

      Your Answer: Common bile duct

      Explanation:

      The posterior relations of the head of the pancreas include: the inferior vena cava, the common bile duct, the renal veins, the right crus of the diaphragm and the aorta.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      9.3
      Seconds
  • Question 126 - A 62-year-old male patient in the intensive care unit was found to have...

    Correct

    • A 62-year-old male patient in the intensive care unit was found to have a low serum phosphate level. What is the serum level of phosphate which is considered as normal in adults?

      Your Answer: 0.8–1.45 mmol/l

      Explanation:

      After calcium, phosphorus is the most plentiful mineral in the human body. It is an important and vital element which our body needs to complete many physiologic processes , such as filtering waste and repairing cells. Phosphorus helps with bone growth and approximately 85% of phosphate in the body is contained in bone. Phosphate is involved in energy storage, and nerve and muscle production. A normal range of plasma phosphate in adults teenagers generally from 0.8 mmol/l to 1.45 mmol/l. The normal range varies depending on age. Infants and children have higher phosphorus levels because more of this mineral is needed for their normal growth and bone development.

    • This question is part of the following fields:

      • Fluids & Electrolytes
      • Pathology
      4.6
      Seconds
  • Question 127 - Different portions of the renal tubule have varying degrees of water permeability. Which...

    Correct

    • 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: 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).

    • This question is part of the following fields:

      • Physiology
      • Renal
      6.4
      Seconds
  • Question 128 - QT interval in the electrocardiogram of a healthy individual is normally: ...

    Incorrect

    • QT interval in the electrocardiogram of a healthy individual is normally:

      Your Answer: 0.05 s

      Correct Answer: 0.40 s

      Explanation:

      QT interval extends from beginning of the QRS complex till the end of he T-wave and normally lasts for 0.40 s. It is important in the diagnosis of long-QT and short-QT syndrome. The QT interval varies on the basis of heart rate and may need to be corrected.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      9
      Seconds
  • Question 129 - Which of the following is a potential cause of a positive D-dimer assay?...

    Correct

    • Which of the following is a potential cause of a positive D-dimer assay?

      Your Answer: Deep venous thrombosis

      Explanation:

      A D-dimer test is performed to detect and diagnose thrombotic conditions and thrombosis. A negative result would rule out thrombosis and a positive result although not diagnostic, is highly suspicious of thrombotic conditions like a deep vein thrombosis, pulmonary embolism as well as DIC.

    • This question is part of the following fields:

      • General
      • Physiology
      5
      Seconds
  • Question 130 - A surgeon performing a thymectomy to remove a malignant thymoma is careful to...

    Correct

    • A surgeon performing a thymectomy to remove a malignant thymoma is careful to avoid damaging an important nerve lying around the arch of the aorta. Which nerve is the surgeon trying to preserve?

      Your Answer: Left Vagus

      Explanation:

      The left vagus nerve lies on the lateral surface of the aortic arch. The left recurrent laryngeal nerve arises from the vagus and loops around the arch of the aorta. This nerve is at risk of injury during surgery.

      The right and left phrenic nerves, being lateral to the vagus, do not loop around the arch of the aorta.

      The sympathetic trunks, both right and left, are located in the posterior chest; not near the aortic arch.

      The right vagus: not involved with the aortic arch.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      10.5
      Seconds
  • Question 131 - Which of the following compensatory parameters is responsible for causing an increase in...

    Correct

    • Which of the following compensatory parameters is responsible for causing an increase in the blood pressure in a 30 year old patient with a BP of 40 mmHg?

      Your Answer: Baroreceptor reflex

      Explanation:

      The baroreflex or baroreceptor reflex is one of the body’s homeostatic mechanisms for regulating blood pressure. It provides a negative feedback response in which an elevated blood pressure will causes blood pressure to decrease; similarly, decreased blood pressure depresses the baroreflex, causing blood pressure to rise. The system relies on specialised neurones (baroreceptors) in the aortic arch, carotid sinuses and elsewhere to monitor changes in blood pressure and relay them to the brainstem. Subsequent changes in blood pressure are mediated by the autonomic nervous system. Baroreceptors include those in the auricles of the heart and vena cava, but the most sensitive baroreceptors are in the carotid sinuses and aortic arch. The carotid sinus baroreceptors are innervated by the glossopharyngeal nerve (CN IX); the aortic arch baroreceptors are innervated by the vagus nerve (CN X).

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      12.7
      Seconds
  • Question 132 - What is the basic chemical reaction that takes place in the breakdown of...

    Correct

    • What is the basic chemical reaction that takes place in the breakdown of complex foodstuffs?

      Your Answer: Hydrolysis

      Explanation:

      Breakdown of complex food into simpler compounds is achieved by hydrolysis, with the help of different enzymes specific for different compounds.

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      19.6
      Seconds
  • Question 133 - The stomach is an organ that is divided into several important anatomical parts....

    Correct

    • 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: 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.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      18.6
      Seconds
  • Question 134 - A 55-year old gentleman presented to the doctor with worsening dysphagia for both...

    Correct

    • A 55-year old gentleman presented to the doctor with worsening dysphagia for both solids and liquids over 6 months. This was associated with regurgitation of undigested food and occasional chest pain. Barium swallow revealed distal oesophageal dilatation with lack of peristalsis in the distal two-third oesophagus. The likely diagnosis is:

      Your Answer: Achalasia

      Explanation:

      Achalasia is an oesophageal motility disorder where inappropriate contractions in the oesophagus lead to reduced peristalsis and failure of the lower oesophageal sphincter to relax properly in response to swallowing. Classical triad of symptoms include dysphagia to fluids followed by solids, chest pain and regurgitation of undigested food. Other symptoms include belching, hiccups, weight loss and cough. Diagnosis is by:

      – X-ray with a barium swallow or oesophagography : narrowing at the gastroesophageal junction (‘bird/parrot beak’ or ‘rat tail’ appearance) and various degrees of mega-oesophagus (oesophageal dilatation) as the oesophagus is gradually stretched by retained food. Effectiveness of treatment can be measured with a 5-minute timed barium swallow.

      – Manometry – probe measures the pressure waves in different parts of oesophagus and stomach while swallowing.

      – Endoscopy

      – CT scan to exclude other causes like malignancy

      – Pathological examination showing defect in the nerves which control oesophageal motility (myenteric plexus).

      In Chagas disease, there is destruction of ganglion cells by Trypanosoma cruzi.

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      50
      Seconds
  • Question 135 - An organ transplant patient may be at risk of developing which type of...

    Correct

    • An organ transplant patient may be at risk of developing which type of cancer?

      Your Answer: Skin cancer

      Explanation:

      The most common malignancies encountered in the post–solid organ transplant setting are non-melanoma skin cancers, post-transplant lymphoproliferative disorders and Kaposi’s sarcoma (KS). The pathogenesis of these tumours is likely related to the immunosuppressive drugs used post-transplantation and subsequent viral infection.

    • This question is part of the following fields:

      • Neoplasia
      • Pathology
      3.5
      Seconds
  • Question 136 - A 25 year old man presented with a history of headache and peripheral...

    Correct

    • A 25 year old man presented with a history of headache and peripheral cyanosis. He had been living in the Himalayas for 6 months prior to this. What is the reason for his condition?

      Your Answer: Physiological polycythaemia

      Explanation:

      Polycythaemia is a condition that results in an increase in the total number of red blood cells (RBCs) in the blood. It can be due to myeloproliferative syndrome or due to chronically low oxygen levels or rarely malignancy. In primary polycythaemia/polycythaemia vera the increase is due to an abnormality in the bone marrow, resulting in increases RBCs, white blood cells (WBCs) and platelets. In secondary polycythaemia the increase occurs due to high levels of erythropoietin either artificially or naturally. The increase is about 6-8 million/cm3 of blood. A type of secondary polycythaemia is physiological polycythaemia where people living in high altitudes who are exposed to hypoxic conditions produce more erythropoietin as a compensatory mechanism for thin oxygen and low oxygen partial pressure.

    • This question is part of the following fields:

      • General
      • Physiology
      3.9
      Seconds
  • Question 137 - A 35 year-old man presents with high grade fever for 7 days after...

    Correct

    • A 35 year-old man presents with high grade fever for 7 days after returning from a trip to India. He tested positive for widal test. What is the most likely organism that caused his fever?

      Your Answer: Salmonella typhi

      Explanation:

      Typhoid fever is caused by virulent bacteria called Salmonella typhi. Salmonella typhi spread through contaminated food or water and occasionally through direct contact with someone who is infected.

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      2.9
      Seconds
  • Question 138 - Which antibiotic acts by inhibiting protein synthesis? ...

    Correct

    • Which antibiotic acts by inhibiting protein synthesis?

      Your Answer: Erythromycin

      Explanation:

      Penicillins and cephalosporins (e.g. cefuroxime, cefotaxime, ceftriaxone) inhibit bacterial cell wall synthesis through the inhibition of peptidoglycan cross-linking.

      Macrolides (e.g. erythromycin), tetracyclines, aminoglycosides and chloramphenicol act by interfering with bacterial protein synthesis.

      Sulphonamides (e.g. trimethoprim, co-trimoxazole) work by inhibiting the synthesis of nucleic acid

    • This question is part of the following fields:

      • Pharmacology; Microbiology
      • Physiology
      12.8
      Seconds
  • Question 139 - Out of the following options, which malignancy has the highest potential for multicentricity?...

    Correct

    • Out of the following options, which malignancy has the highest potential for multicentricity?

      Your Answer: Transitional cell carcinoma

      Explanation:

      Transitional cell carcinomas can arise anywhere in the urothelium lining the urinary tract; and hence are known to be multicentric and recur commonly. Prostatic adenocarcinoma most commonly involves the posterior lobe of the prostate gland. Although renal cell carcinomas occasionally show multicentricity, it is not common. Penile carcinomas are usually locally infiltrative lesions. Wilm’s tumours are usually solitary, but can be bilateral or multicentric in 10% cases. Small cell carcinoma of lung and teratomas are usually solitary.

    • This question is part of the following fields:

      • Pathology
      • Renal
      6.4
      Seconds
  • Question 140 - Routine evaluation of a 38 year old gentleman showed a slightly lower arterial...

    Correct

    • Routine evaluation of a 38 year old gentleman showed a slightly lower arterial oxygen [pa(O2)] than the alveolar oxygen [pA(O2)]. This difference is:

      Your Answer: Is normal and due to shunted blood

      Explanation:

      Blood that bypasses the ventilated parts of lung and enters the arterial circulation directly is known as shunted blood. It happens in normal people due to mixing of arterial blood with bronchial and some myocardial venous blood (which drains into the left heart). Diffusion limitation and reaction velocity with haemoglobin are immeasurably small. CO2 unloading will not affect the difference between alveolar and arterial p(O2). A large VSD will result in much lower arterial O2 as compared to alveolar O2.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      7.6
      Seconds
  • Question 141 - The muscles of the superficial posterior compartment of the leg insert into the:...

    Correct

    • The muscles of the superficial posterior compartment of the leg insert into the:

      Your Answer: Calcaneus

      Explanation:

      The muscles of the superficial posterior compartment of the leg form the characteristic ‘calf’ shape of the posterior leg and include the gastrocnemius, soleus and plantaris. The gastrocnemius and soleus together form a muscular mass which is occasionally described as the triceps surae; its tendon of insertion is the tendo calcaneus. The tendo calcaneus is the thickest and strongest in the body and together with the tendon of the plantaris muscle is inserted into the posterior part of the calcaneus.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      7
      Seconds
  • Question 142 - Which of the following is true about a patient who has undergone total...

    Correct

    • Which of the following is true about a patient who has undergone total colectomy and ileostomy?

      Your Answer: Following total colectomy and ileostomy, the volume and water content of ileal discharge decreases over time

      Explanation:

      After a patient has undergone total colectomy and ileostomy, the volume of ileal discharge, along with its water content gradually decreases over time. Post surgery, most patients can live a normal life. Iron and vitamin B12 absorption do not take place in the colon and hence are not affected significantly by a colectomy.

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      9
      Seconds
  • Question 143 - A 30-year-old woman is diagnosed with Hodgkin's lymphoma. Which of the following chemotherapy...

    Correct

    • A 30-year-old woman is diagnosed with Hodgkin's lymphoma. Which of the following chemotherapy regimens would be used in this case?

      Your Answer: ABVD

      Explanation:

      ABVD is a chemotherapy regimen used in the first-line treatment of Hodgkin’s lymphoma. It consists of concurrent treatment with the chemotherapy drugs, adriamycin, bleomycin, vinblastine and dacarbazine. It supplanted the older MOPP protocol.

    • This question is part of the following fields:

      • Pathology
      • Pharmacology
      8.6
      Seconds
  • Question 144 - The blood-brain barrier is a membrane that separates the circulating blood from the...

    Correct

    • 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: 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.

    • This question is part of the following fields:

      • Fluids & Electrolytes
      • Physiology
      15.9
      Seconds
  • Question 145 - During a laparoscopic surgery, the surgeon visualizes the medical umbilical folds on the...

    Correct

    • During a laparoscopic surgery, the surgeon visualizes the medical umbilical folds on the deep surface of the anterior abdominal wall. What causes the medial umbilical folds?

      Your Answer: Obliterated umbilical arteries

      Explanation:

      The medial umbilical ligament is a structure found on the deep surface of the anterior abdominal wall and is covered by the medial umbilical folds. It is a paired structure that represents the remnants of the fetal umbilical artery. They have no role in humans after birth other than to be used as a landmark for exploring the medial inguinal fossa during laparoscopic inguinal hernia repair.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      9.2
      Seconds
  • Question 146 - A 50 year old woman presented with excessive bleeding after an inguinal hernia...

    Correct

    • 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: 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.

    • This question is part of the following fields:

      • General
      • Physiology
      7.3
      Seconds
  • Question 147 - Low molecular weight heparin (LMWH) has less side effects than heparin and is...

    Incorrect

    • Low molecular weight heparin (LMWH) has less side effects than heparin and is used in the prophylaxis and treatment of venous and arterial thrombotic disorders. Which of the following is LMWHs mechanism of action?

      Your Answer: Inhibition of synthesis of vitamin K-dependent clotting factors

      Correct Answer: Inhibition of factor Xa

      Explanation:

      Low molecular weight heparin (LMWH) is a anticoagulant that differs from normal heparin in that it has only short chains of polysaccharide. LMWH inhibits thrombin formation by converting antithrombin from a slow to a rapid inactivator of coagulation factor Xa.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      136
      Seconds
  • Question 148 - When exposing the right saphenofemoral junction for flush-ligation of the saphenous vein, which...

    Incorrect

    • When exposing the right saphenofemoral junction for flush-ligation of the saphenous vein, which of the following is the most likely to be seen passing through this opening?

      Your Answer: Genitofemoral nerve

      Correct Answer: Superficial external pudendal artery

      Explanation:

      The saphenous opening is an oval opening in the fascia lata. It is covered by the cribriform fascia and It is so called because it is perforated by the great saphenous vein and by numerous blood and lymphatic vessels and the superficial external pudendal artery pierces it.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      28.8
      Seconds
  • Question 149 - At which cervical level does the common carotid artery bifurcate into the internal...

    Incorrect

    • At which cervical level does the common carotid artery bifurcate into the internal and external carotid arteries?

      Your Answer: C8

      Correct Answer: C4

      Explanation:

      The common carotid arteries are present on the left and right sides of the body. These arteries originate from different sources, but follow symmetrical courses. The right common carotid originates in the neck from the brachiocephalic trunk; the left from the aortic arch in the thorax. These split into the external and internal carotid arteries at the upper border of the thyroid cartilage, at around the level of the fourth cervical vertebra.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      12.6
      Seconds
  • Question 150 - What is the action of the muscle of the orbit that originates on...

    Incorrect

    • What is the action of the muscle of the orbit that originates on the lesser wing of the sphenoid bone, just above the optic foramen?

      Your Answer: Elevation of the eyeball

      Correct Answer: Elevation of the upper eyelid

      Explanation:

      The levator palpebrae superioris is the muscle in the orbit that elevates the superior (upper) eyelid. The levator palpebrae superioris originates on the lesser wing of the sphenoid bone, just above the optic foramen and receives somatic motor input from the ipsilateral superior division of the oculomotor nerve.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      56.1
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Anatomy (43/59) 73%
Lower Limb (10/11) 91%
Embryology (2/2) 100%
Pathology (40/44) 91%
Renal (10/10) 100%
Endocrine (4/4) 100%
Physiology (43/47) 91%
Abdomen (10/13) 77%
Women's Health (1/1) 100%
Cell Injury & Wound Healing (3/3) 100%
Cardiovascular (5/6) 83%
Thorax (6/8) 75%
Head & Neck (10/20) 50%
General (13/14) 93%
Gastroenterology (8/9) 89%
Fluids & Electrolytes (6/6) 100%
Neurology (7/8) 88%
Neoplasia (4/4) 100%
Cell Injury & Wound Healing; Haematology (1/1) 100%
Inflammation & Immunology (2/3) 67%
Pelvis (2/2) 100%
Microbiology (4/5) 80%
Upper Limb (3/3) 100%
Respiratory (4/4) 100%
Cell Injury & Wound Healing; Respiratory (1/1) 100%
Neoplasia; Orthopaedics (1/1) 100%
Orthopaedics (1/1) 100%
Haematology (1/2) 50%
Neoplasia; Urology (0/1) 0%
Pharmacology (3/3) 100%
Cell Injury & Wound Healing; Female Health (1/1) 100%
Gastrointestinal; Hepatobiliary (1/1) 100%
Cell Injury & Wound Healing; Cardiovascular (1/1) 100%
Pharmacology; Microbiology (1/1) 100%
Passmed