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Question 1
Correct
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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.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 2
Correct
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A Jewish man was diagnosed with haemophilia C. Which of the following factors is deficient in this form of haemophilia?
Your Answer: Factor XI
Explanation:Haemophilia C, also known as plasma thromboplastin antecedent (PTA) deficiency or Rosenthal syndrome, is a condition caused by the deficiency of the coagulation factor XI. The condition is rare and it is usually found in Ashkenazi Jews.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 3
Correct
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A 7-year-old boys undergoes a testicular biopsy after a tumour is found in his right testis. Elements similar to hair and teeth are found in it. What kind of tumour is this?
Your Answer: Teratoma
Explanation:A teratoma is a tumour containing tissue elements that are similar to normal derivatives of more than one germ layer. They usually contain skin, hair, teeth and bone tissue and are more common in children, behaving as a benign tumour. After puberty, they are regarded as malignant and can metastasise.
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This question is part of the following fields:
- Pathology
- Urology
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Question 4
Correct
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In a cardiac cycle, what event does the closing of atrioventricular (AV) valves coincide with?
Your Answer: First heart sound
Explanation:In the cardiac cycle, the closing of the atrioventricular (AV) valves coincides with the onset of ventricular systole. This event marks the beginning of the isovolumetric contraction phase, where the ventricles begin to contract, but the volume of blood in the ventricles remains the same because both the AV valves and the semilunar valves (aortic and pulmonary valves) are closed. The closing of the AV valves produces the first heart sound, known as “S1” or “lub.”
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 5
Correct
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Which of the following is responsible for the maximum increase in total peripheral resistance on sympathetic stimulation?
Your Answer: Arterioles
Explanation:Arterioles are also known as the resistance vessels as they are responsible for approximately half the resistance of the entire systemic circulation. They are richly innervated by the autonomic nervous system and hence, will bring about the maximum increase in peripheral resistance on sympathetic stimulation.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 6
Incorrect
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In which of the following compartments of the femoral sheath is the femoral artery located?
Your Answer: Medial compartment
Correct Answer: Lateral compartment
Explanation:The femoral sheath also known as the crural sheath is made up of three compartments; lateral, intermediate and the medial. The femoral artery is contained in the lateral compartment of the femoral sheath while the femoral vein is in the intermediate compartment.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 7
Correct
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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.
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This question is part of the following fields:
- General
- Physiology
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Question 8
Correct
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The chest X-ray of an 10-year-old boy, that presented with low-grade fever and cough, revealed hilar enlargement and parenchymal consolidation in the middle lobes. These X-ray findings are more typical for which of the following diagnoses?
Your Answer: Pulmonary tuberculosis
Explanation:Primary pulmonary tuberculosis is seen in patients exposed to Mycobacterium tuberculosis for the firs time. The main radiographic findings in primary pulmonary tuberculosis include homogeneous parenchymal consolidation typically in the lower and middle lobes, lymphadenopathy, miliary opacities and pleural effusion.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 9
Correct
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The dura mater is a thick membrane that is the outermost of the three layers of the meninges. Which of the following foramen transmits the dura mater?
Your Answer: Foramen magnum
Explanation:The foramen magnum is found in the most inferior part of the posterior cranial fossa . It is traversed by vital structures including the medulla oblongata . Its contents include the following: medulla oblongata, meninges (arachnoid, dura and pia mater), spinal root of the accessory nerve, vertebral arteries, anterior and posterior spinal arteries, tectorial membrane and alar ligaments .
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 10
Correct
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What is the chief ligament preventing posterior sliding of the tibia on the femur ?
Your Answer: Posterior cruciate
Explanation:The posterior cruciate ligament is attached to the posterior intercondyloid fossa of the tibia and the lateral and front part of the medial condyle of the femur. It resists sliding of the tibia posteriorly.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 11
Correct
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13 year old girl developed sun burnt cheeks after spending the day playing on the beach. What is the underlying mechanism to her injury?
Your Answer: Free radical injury
Explanation:Free radicals are a by-product of chemical reactions with an unpaired electron in their outer most shell. They are capable of causing wide spread damage to cells. They can cause autolytic reactions thereby converting the reactants into free radicals. By absorbing sun light, the energy is used to hydrolyse water into hydroxyl (OH) and hydrogen (H) free radicals which can cause injury by lipid peroxidation of membranes, oxidative modification of proteins and damage to the DNA structure.
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This question is part of the following fields:
- Cell Injury & Wound Healing; Dermatology
- Pathology
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Question 12
Incorrect
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An old man presented with atrophy of the thenar eminence despite the sensation over it still being intact. What is the injured nerve in this case?
Your Answer: Musculocutaneous nerve
Correct Answer: Median nerve
Explanation:Atrophy of the thenar muscles means injury to the motor supply of these muscles. The nerve that sends innervation to it is the median nerve. But the median nerve does not provide sensory innervation to the overlying skin so sensation is spared.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 13
Correct
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An experiment is carried out to observe engulfment and phagocytosis of microbes. Strep pneumoniae are added to a solution of leukocytes with a substance added to enhance the process of phagocytosis. What is this substance?
Your Answer: Complement C3b
Explanation:C3b is cleaved from C3 complement with the help of the enzyme C3- convertase. It binds to the cell surface of the offending substance and opsonizes it. This makes it easy for the phagocytes to detect and eliminate them.
IgM does not act as an opsonin but igG does.
Selectins aid leukocytes to bind to the endothelial surfaces.
C5a is a chemo-attractant and histamine a vasodilator.
NADPH oxidises offending substance after phagocytosis within the macrophage.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 14
Correct
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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.
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This question is part of the following fields:
- Pathology
- Renal
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Question 15
Incorrect
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Which is the correct superficial to deep order of structures that would be affected following a knife wound to the lateral aspect of the knee?
Your Answer: Skin, popliteus tendon, fibular collateral ligament, lateral meniscus
Correct Answer: skin, fibular collateral ligament, popliteus muscle tendon, lateral meniscus
Explanation:Skin, fibular collateral ligament, popliteus muscle tendon and lateral meniscus is the correct order of structures covering the lateral aspect of the knee joint from a superficial to deep.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 16
Correct
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A teenager presents with pain and swelling in a limb which increases after activity. X-rays reveal an expansible, eccentric, lytic lesion in the metaphysis distally in the affected bone surrounded by new bone. What is the most likely diagnosis?
Your Answer: Aneurysmal bone cyst
Explanation:Aneurysmal bone cysts tend to develop in patients younger than 20 years old. They usually occur in the metaphyseal region of long bones, and are cystic lesions composed of numerous blood filled channels that grow slowly. In X-rays, they show up as circumscribed lesions, sometimes surrounded by new bone.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 17
Correct
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Which one of the following is a derivative of the midgut?
Your Answer: Caecum
Explanation:The primary intestinal loop is formed from the midgut which gives rise to the distal half of the duodenum, the jejunum, ascending colon, proximal two thirds of the transverse colon and the ileum.
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This question is part of the following fields:
- Anatomy
- Embryology
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Question 18
Incorrect
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The following structures DO NOT lie between the layers of the mesosalpinx except for the?
Your Answer: Round ligament of the uterus
Correct Answer: Fallopian tube
Explanation:Mesosalpinx is the portion of the broad ligament that stretches from the fallopian tube to the ovary and contains the uterine tubes between it’s layers.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 19
Correct
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Whilst snorkelling, a 30-year old gentleman has the respiratory rate of 10/min, tidal volume of 550 ml and an effective anatomical dead space of 250 ml. What is his alveolar ventilation?
Your Answer: 3000 ml/min
Explanation:Alveolar ventilation is the amount of air reaching the alveoli per minute. Alveolar ventilation = respiratory rate × (tidal volume – anatomical dead space volume). Thus, alveolar ventilation = 10 × (550 − 250) = 3000 ml/min.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 20
Incorrect
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A 26-year-old female patient had the following blood report: RBC count = 4. 0 × 106/μl, haematocrit = 27% and haemoglobin = 11 g/dl, mean corpuscular volume (MCV) = 80–100 fl, mean corpuscular haemoglobin concentration (MCHC) = 31–37 g/dl. Which of the following is correct regarding this patient’s erythrocytes:
Your Answer: Normal MCHC
Correct Answer: Normal MCV
Explanation:MCV is the mean corpuscular volume and it is calculated from the haematocrit and the RBC count. It is normally 90 fl. Mean corpuscular haemoglobin concentration (MCHC) [g/dl] = haemoglobin [g/dl]/haematocrit = 11/0.27 = 41 g/dl and is higher than normal range (32 to 36 g/dL).
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This question is part of the following fields:
- General
- Physiology
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Question 21
Incorrect
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A 34-year old gentleman presented with acute pancreatitis to the emergency department. On enquiry, there was found to be a history of recurrent pancreatitis, eruptive xanthomas and raised plasma triglyceride levels associated with chylomicrons. Which of the following will be found deficient in this patient?
Your Answer: Low-density lipoprotein (LDL) receptors
Correct Answer: Lipoprotein lipase
Explanation:The clinical features mentioned here suggest the diagnosis of hypertriglyceridemia due to lipoprotein lipase (LPL) deficiency. LPL aids in hydrolysing the lipids in lipoproteins into free fatty acids and glycerol. Apo-CII acts as a co-factor. Deficiency of this enzyme leads to hypertriglyceridemia.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 22
Incorrect
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The renal cortex and medulla, if seen under the microscope, is lacking one of the following:
Your Answer: Henle’s loop
Correct Answer: Squamous epithelium
Explanation:Capillaries, Henle’s loop, collecting ducts, Bertin columns and type IV collagen in glomerular basement membrane are all structures present in the renal cortex or medulla. The squamous epithelium is the only one that is lacking in both the renal cortex and medulla, because normally it is not found above the outer urethra.
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This question is part of the following fields:
- Pathology
- Renal
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Question 23
Incorrect
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Leakage from a silicone breast implant can lead to:
Your Answer: Fat necrosis
Correct Answer: Pain and contracture
Explanation:Breast implants are mainly: saline-filled and silicone gel-filled. Complications include haematoma, fluid collections, infection at the surgical site, pain, wrinkling, asymmetric appearance, wound dehiscence and thinning of the breast tissue.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 24
Incorrect
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Regarding the venous drainage of the heart which of these is correct?
Your Answer: The anterior cardiac veins begin over the anterior surface of the left ventricle, cross over the atrioventricular groove (coronary groove) and directly drain into the left atrium
Correct Answer: The great cardiac vein is the largest tributary of the coronary sinus and this vein starts at the apex of the heart and ascends with the anterior ventricular branch of the left coronary artery
Explanation:Most of the veins of the heart open into the coronary sinus. This is a wide venous channel, about 2.25 cm in length, situated in the posterior part of the coronary sulcus and covered by muscular fibres from the left atrium. Its tributaries are the great, small and middle cardiac veins, the posterior vein of the left ventricle and the oblique vein of the left atrium. The great cardiac vein is the largest tributary of the coronary sinus.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 25
Correct
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During an OSCE exam a medical student is asked to locate the sternal angle. The sternal angle is a land mark for locating the level of the:
Your Answer: Second costal cartilage
Explanation:The sternal angle, a key landmark used in the clinic for auscultating for heart sounds, is the point of attachment of the costal cartilage of rib 2 to the sternum. It thus corresponds to the location of the second rib. A horizontal plane through the sternal angle traverses the T4/T5 intervertebral disc and marks the inferior boundary of the superior mediastinum.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 26
Incorrect
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After a cerebral infarction, which of these histopathogical findings is most likely to be found?
Your Answer: Coagulative necrosis
Correct Answer: Liquefactive necrosis
Explanation:The brain has a high lipid content and typically undergoes liquefaction with ischaemic injury, because it contains little connective tissue but high amounts of digestive enzymes.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 27
Incorrect
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Skin infiltration by neoplastic T lymphocytes is seen in:
Your Answer: Hairy cell leukaemia
Correct Answer: Mycosis fungoides
Explanation:Mycosis fungoides is a chronic T-cell lymphoma that involves the skin and less commonly, the internal organs such as nodes, liver, spleen and lungs. It is usually diagnosed in patients above 50 years and the average life expectancy is 7-10 years. It is insidious in onset and presents as a chronic, itchy rash, eventually spreading to involve most of the skin. Lesions are commonly plaque-like, but can be nodular or ulcerated. Symptoms include fever, night sweats and weight loss. Skin biopsy is diagnostic. However, early cases may pose a challenge due to fewer lymphoma cells. The malignant cells are mature T cells (T4+, T11+, T12+). The epidermis shows presence of characteristic Pautrier’s micro abscesses are present in the epidermis.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 28
Correct
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The muscles of the superficial posterior compartment of the leg insert into the:
Your Answer: Calcaneus
Explanation:The muscles of the superficial posterior compartment of the leg form the characteristic ‘calf’ shape of the posterior leg and include the gastrocnemius, soleus and plantaris. The gastrocnemius and soleus together form a muscular mass which is occasionally described as the triceps surae; its tendon of insertion is the tendo calcaneus. The tendo calcaneus is the thickest and strongest in the body and together with the tendon of the plantaris muscle is inserted into the posterior part of the calcaneus.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 29
Correct
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Which of the following diseases is caused by intra-articular and/or extra-articular deposition of calcium pyrophosphate dihydrate (CPPD) crystals, due to unknown causes?
Your Answer: Pseudogout
Explanation:Pseudogout or chondrocalcinosis is a rheumatological disease caused by the accumulation of crystals of calcium pyrophosphate dihydrate (CPPD) in the connective tissues. It is frequently associated with other conditions, such as trauma, amyloidosis, gout, hyperparathyroidism and old age, which suggests that it is secondary to degenerative or metabolic changes in the tissues. The knee is the most commonly affected joint. It causes symptoms similar to those of rheumatoid arthritis or osteoarthritis.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 30
Correct
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In the emergency room, a nurse was introducing a catheter into the patients femoral vein for rapid fluid therapy. The femoral vein is situated inside the femoral sheath. Which of the following is true about that sheath?
Your Answer: The medial compartment is called the femoral canal
Explanation:The femoral sheath is situated ,4cm below the inguinal ligament. It is a prolongation of the abdominal fascia. The anterior wall is a prolongation of the transversalis fascia and the posterior wall, the iliac fascia. It is divided by two vertical septa into 3 compartments, lateral, intermediate, and medial. The medial compartment is known as the femoral canal and contains some lymphatic vessels. The lateral one contains the femoral artery and the intermediate one contains the femoral vein.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 31
Correct
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Bloody discharge from the nipple of a 40-year old woman with no obvious lump or abnormality on mammography is suggestive of:
Your Answer: Intraductal papilloma
Explanation:A small benign tumour, namely intraductal papilloma is most common in women between 35-55 years of age. It is also the commonest cause of spontaneous discharge from a single duct. A lump below the nipple may be sometimes palpable. Ultrasound and ductography are useful investigations., along with cytology of discharge to assess the presence of malignant cells. Confirmation is by breast biopsy.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 32
Incorrect
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The petrous part of the internal carotid artery is located inside of which cranial bone?
Your Answer: Maxillary
Correct Answer: Temporal
Explanation:The petrous segment, or C2, of the internal carotid is that which is inside the petrous part of the temporal bone. This segment extends until the foramen lacerum. The petrous portion classically has three sections: an ascending, or vertical portion; the genu, or bend; and the horizontal portion.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 33
Incorrect
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A 55-year-old man underwent CT scan of the whole abdomen. The result showed renal cell carcinoma with a tumour size of 7cm and extension into the regional lymph. What is the clinical stage of his renal cell cancer?
Your Answer: Stage IV
Correct Answer: Stage III
Explanation:Renal cell carcinoma is a kidney cancer that originates in the lining of the proximal convoluted tubule. It is the most common type of kidney cancer in adults, responsible for approximately 90–95% of cases. Renal cell carcinomas can be staged by using the American Joint Committee on Cancer (AJCC) TNM (tumour-node-metastasis) classification, as follows: Stage I: tumours that are 7 cm or smaller and confined to the kidney, Stage II: tumours that are larger than 7 cm but still confined to the kidney, Stage III: tumours extending into the renal vein or vena cava, involving the ipsilateral adrenal gland and/or perinephric fat, or which have spread to one local lymph node and Stage IV: tumours extending beyond Gerota’s fascia, to more than one local node, or with distant metastases Recent literature has questioned whether the cut-off in size between stage I and stage II tumours should be 5 cm instead of 7 cm. The patient’s cancer in this case is stage III.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 34
Incorrect
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Which of the following malignancies is associated with the development of Lambert-Eaton myasthenic syndrome?
Your Answer: Brain Cancer
Correct Answer: Lung cancer
Explanation:Lambert–Eaton myasthenic syndrome is a rare disorder of the neuromuscular junction. It can occur as a solitary diagnosis but it can also occur as a paraneoplastic syndrome associated with lung cancer, particularly small-cell histology. It can also be associated with other cancers such as lymphoma, non-Hodgkin’s lymphoma, T-cell leukaemia, non-small-cell lung cancer, prostate cancer and thymoma.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 35
Incorrect
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A surgical registrar performing an adrenalectomy procedure on the left suprarenal gland of a 25 - year old male patient, accidentally jabbed and injured a vital structure that lies anterior to the left suprarenal organ. Which of the following was the structure most likely injured?
Your Answer: Liver
Correct Answer: Pancreas
Explanation:The adrenal (suprarenal) glands are organs of the endocrine system located on top of each of the kidneys. The left suprarenal gland, in question, is crescent in shape and slightly larger than the right suprarenal gland. It is posteriorly located to the lateral aspect of the head of the pancreas which is thus the most likely to be injured. The other organs like the duodenum, liver and the inferior vena cava are related to the right suprarenal gland. The spleen and the colon are not in close proximity with the left suprarenal gland and are not likely to be the organs injured.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 36
Correct
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What is the most likely cause of bitemporal hemianopia?
Your Answer: Prolactinoma
Explanation:Prolactinoma is the mot common pituitary adenoma; leading to hyperprolactinaemia. By virtue of their size, macroprolactinomas press on the adjacent structures leading to headaches and loss of vision due to the pressure effect on optic chiasm. Women notice a change in their menstrual cycle due to raised prolactin levels. In comparison, the problem goes unnoticed in men in the initial stages. Craniopharyngioma is a less common space-occupying lesions affecting children and young adults.
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This question is part of the following fields:
- Endocrine
- Pathology
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Question 37
Correct
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A patient with Paget's disease of the bone is predisposed to developing which type of cancer?
Your Answer: Osteosarcoma
Explanation:Paget’s disease of bone (PDB) is a focal disorder of bone. It is presumed benign in nature and mediated by abnormal osteoclast function. However osteosarcomas may occur in <1% of patients with Paget's disease of the bone. Osteosarcomas are osteogenic in origin, and consistently arise in sites of pagetic bone. This is not to be confused with Paget's disease of the breast.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 38
Correct
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C5a (a complement component) is a potent?
Your Answer: Anaphylotoxin
Explanation:C5a is a strong chemoattractant as well as an anaphylotoxin and is involved in the recruitment of inflammatory cells such as neutrophils, eosinophils, monocytes, and T lymphocytes. It is also involved in activation of phagocytic cells, release of granule-based enzymes and generation of oxidants. All of which contribute to innate immune functions.
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This question is part of the following fields:
- General
- Physiology
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Question 39
Correct
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The absence of which of the following components characterizes the grey platelet syndrome (GPS)?
Your Answer: Alpha granules
Explanation:Grey platelet syndrome (GPS) is a rare inherited bleeding disorder associated with an almost total absence of α-granules and their contents. The syndrome is characterised by thrombocytopenia, enlarged platelets that have a grey appearance, myelofibrosis, and splenomegaly. Alpha granules store proteins and growth factors that promote platelet adhesiveness and wound healing. Patients with GPS develop symptoms and signs such as easy bruising, prolonged bleeding, and nose bleeds.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 40
Incorrect
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The midgut loop, also called the primary intestinal loop in a developing embryo, is formed when the midgut bends around which of the following arteries?
Your Answer: Proper hepatic
Correct Answer: Superior mesenteric
Explanation:In a developing foetus, the midgut develops to form most of the intestines. During this development process, the midgut usually bends around the superior mesenteric artery and forms what is referred to as the midgut loop.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 41
Incorrect
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A 70-year-old male who has smoked since his teens complains of progressive shortness of breath and a persistent cough. He is diagnosed with COPD. Which of the following abnormalities is most likely to be present in his pulmonary function tests?
Your Answer: Increased FEV1/FVC
Correct Answer: Increased residual volume
Explanation:Chronic obstructive pulmonary disease (COPD) is a type of obstructive lung disease characterized by long-term poor airflow. The main symptoms include shortness of breath and cough with sputum production. The best diagnostic test for evaluating patients with suspected chronic obstructive pulmonary disease (COPD) is lung function measured with spirometry. Key spirometrical measures may be obtained with a portable office spirometer and should include forced vital capacity (FVC) and the normal forced expiratory volume in the first second of expiration (FEV1). The ratio of FEV1 to forced vital capacity (FEV1/FVC) normally exceeds 0.75. Patients with COPD typically present with obstructive airflow. Complete pulmonary function testing may show increased total lung capacity, functional residual capacity and residual volume. A substantial loss of lung surface area available for effective oxygen exchange causes diminished carbon monoxide diffusion in the lung (DLco) in patients with emphysema. Tobacco smoking is the most common cause of COPD, with factors such as air pollution and genetics playing a smaller role.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 42
Correct
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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.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 43
Incorrect
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A biopsy taken from the respiratory passage of a 37 year old male, chronic smoker will mostly likely show which cellular adaptation?
Your Answer: Squamous cell hypertrophy
Correct Answer: Stratified squamous metaplasia
Explanation:Metaplasia is a change in the cell type caused in part due to an extrinsic stress on the organ. It involves a change in the surface epithelium from one cell type to the another, most commonly squamous to columnar. This is a reversible process, and removal of the stress should theoretically reverse the surface epithelium back to normal morphology. Respiratory tract metaplasia is a classic example, in which the normal pseudostratified columnar epithelium is replaced by stratified squamous epithelium to better cope with the stress. Under continuous stress metaplasia can progress to dysplasia which is a disordered growth of cells eventually leading to the development of carcinoma.
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This question is part of the following fields:
- Cell Injury & Wound Healing; Respiratory
- Pathology
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Question 44
Incorrect
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Which lymph nodes are likely to be enlarged in a patient who has malignant growth involving the anus?
Your Answer: Pararectal
Correct Answer: Superficial inguinal
Explanation:The lymphatics from the anus, skin of the perineum and the scrotum end in the superficial inguinal nodes. In case of a malignant growth of the anus, the superficial inguinal lymph nodes would most likely be enlarge.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 45
Incorrect
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A 30-year old lady was admitted to the general surgical ward after a diagnosis of perforation of the first part of the duodenum that resulted from a long standing ulcer. If this perforation led to the expulsion of the gastric content that resulted to the erosion of an artery found in this part of the duodenum (the posterior of the first part of the duodenum). Which of the following arteries is this most likely to be?
Your Answer: Superior mesenteric
Correct Answer: Gastroduodenal
Explanation:The proximal part of the duodenum is supplied by the gastroduodenal artery. This artery is found descending behind the first part of the duodenum after branching from the hepatic artery. If gastric content was to be expelled in the posterior portion of the first part of the duodenum, then this artery would be most likely to be damaged. The common hepatic artery and the left gastric artery are branches of the coeliac trunk that are found superior to the duodenum. The proper hepatic artery is a branch of the common hepatic artery also found superior to the duodenum. The superior mesenteric artery is found behind the pancreas as a branch of the aorta that is at the bottom of the L1 level. The right gastric artery arises above the pylorus from the proper hepatic artery and supplies the lesser curvature of the stomach. The intestinal arteries supply the ileum and the jejunum.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 46
Incorrect
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A 70-year old man presents to the surgical out patient clinic with a direct inguinal hernia on the right side. He had undergone and appendicectomy 6 months prior. The examining doctor correlated the development of the hernia to iatrogenic nerve injury that happened during the operation. Which nerve had been injured?
Your Answer: Femoral branch of the genitofemoral
Correct Answer: Ilioinguinal
Explanation:Direct inguinal hernias occur because of weakness in the abdominal muscles. The ilioinguinal nerve is important for innervating the muscles of the lower abdominal wall and damage during appendicectomy therefore prevents the man from being able to contract abdominal muscles to pull the falx inguinalis over the weak fascia.
The genitofemoral nerve innervates the cremaster muscle and injury to it would cause inability to elevate the testes.
The subcostal nerve and the ventral primary ramus of T10 innervate the muscles, skin and fascia of the upper abdominal wall.
The iliohypogastric nerve supplies the skin over the upper part of the buttock behind the area supplied by the subcostal nerve.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 47
Incorrect
-
A 35-year-old ultra marathon runner becomes severely dehydrated and collapses. This patient most likely has:
Your Answer: Low water permeability of collecting duct tubular cells
Correct Answer: Decreased baroreceptor firing rate
Explanation:Baroreceptors are sensors located in the blood vessels of all vertebrate animals. They sense the blood pressure and relay the information to the brain, so that a proper blood pressure can be maintained. Acute dehydration results in decreased plasma volume and increased plasma osmolarity, since more water than salt is lost in sweat. The decrease in plasma volume leads to an inhibition of the baroreceptors and a lower firing rate. The increase in plasma osmolarity leads to increased ADH secretion and high plasma ADH levels, which increases water permeability of collecting duct cells. Therefore more water is reabsorbed by the kidneys and renal water excretion is low.
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This question is part of the following fields:
- Physiology
- Renal
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Question 48
Incorrect
-
A 66-year-old man complains of constant headaches. On physical examination, the only relevant sign is a dark brown mole located on left his arm which has grown in size over the years and is itchy and painful. A MRI of the brain revealed a solitary lesion at the grey-white junction in the right frontal lobe, without ring enhancement. This lesion is most likely to be:
Your Answer: Cerebral abscess
Correct Answer: Metastatic carcinoma
Explanation:The location of the mass at the grey–white junction is typical of a metastasis. The most frequent types of metastatic brain tumours originate in the lung, skin, kidney, breast and colon. These tumour cells reach the brain via the bloodstream. This patient is likely to have skin cancer, which caused the metastatic brain tumour.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 49
Incorrect
-
A young boy fell from a tree, sustaining an injury to the elbow area and damaging the nerve behind the medial epicondyle of the humerus. What is the most likely result from that injury?
Your Answer: General cutaneous sensation over the thenar eminence
Correct Answer: Flexion in the distal interphalangeal joint of digit 5
Explanation:The nerve injured in this situation is the ulnar nerve. It passes posterior to the medial epicondyle of the humerus before going between the two heads of the flexor carpi ulnaris muscle. This nerve supplies the muscles and skin of forearm and hand. At the level of medial epicondyle, the injury will led to paralysis in flexor carpi ulnaris and the ulnar half of the flexor digitorum profundus as well as the palmar interossei and hypothenar muscles in the hand. The correct answer will be that the boy will suffer from inability to flex the distal interphalangeal joint of digit 5
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 50
Incorrect
-
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: Axillary
Correct 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.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 51
Incorrect
-
A cerebellar tremor can be differentiated from a Parkinsonian tremor in that:
Your Answer: It is present at rest
Correct Answer: It only occurs during voluntary movements
Explanation:Cerebellar disease leads to intention tremors, which is absent at rest and appears at the onset of voluntary movements. In comparison, Parkinson’s tremor is present at rest. Frequency of tremor is a less reliable means to differentiate between the two as the oscillation amplitude of the tremor is not constant throughout a voluntary action.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 52
Incorrect
-
When at rest, which of the following will be higher in a marathon runner compared to an untrained individual?
Your Answer: Oxygen consumption
Correct Answer: Cardiac stroke volume
Explanation:Cardiac muscle hypertrophy is seen in trained athletes as compared to the normal population. This hypertrophy results in higher stroke volume at rest and increased cardiac reserve (maximum cardiac output during exercise). However, the cardiac output at rest is almost the same in both trained and untrained people. This is because in trained athletes, the heart rate is slower, even up to 40-50 beats/min. There is minimal affect of athletic training on oxygen consumption and respiratory rate.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 53
Incorrect
-
Lateral medullary syndrome, also known as Wallenberg's syndrome is a neurological condition caused by ischaemia in the lateral part of the medulla oblongata and is commonly associated with numerous neurological symptoms. Which of the following arteries when occluded leads to this condition?
Your Answer: Anterior inferior cerebellar
Correct Answer: Posterior inferior cerebellar
Explanation:The lateral medullary syndrome or Wallenberg’s disease is also known as posterior inferior cerebellar artery syndrome (PICA). This syndrome is a clinical manifestation of the occlusion of the posterior cerebellar artery that results in symptoms of infarction of the lateral medullary oblongata. Other arteries that contribute to blood flow in to this region such are the vertebral artery, superior middle cerebellar and inferior medullary arteries can also result to this syndrome when occluded.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 54
Incorrect
-
A 24-year old, lactating mother presents to the clinic with a tender, 1.5cm mass just below the right nipple, which shows multiple fissures. What finding is likely associated with her condition?
Your Answer: Fibroadenoma
Correct Answer: Staphylococcus aureus infection
Explanation:Breast abscess occur commonly in lactating mothers in the postpartum period due to cracking of the nipple. It is commonly caused due to Staphylococcus aureus infection. Fat necrosis usually results from trauma wherein an ill-defined mass is formed. Ductal carcinomas are malignant masses which are not tender usually, and rare in the young age group. Plasma cell mastitis affect women in an older age group. Sclerosing adenosis is a type of fibrocystic disease which can lead to a tender, cystic mass but no fissuring or cracks are seen in the nipple. Fibroadenoma and lipomas are non-tender, well-defined masses.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 55
Correct
-
Which of the following has the highest content of triglycerides?
Your Answer: Chylomicron
Explanation:Created by the small intestinal cells, chylomicrons are large lipoprotein molecules which transport lipids to the liver, adipose, cardiac and skeletal tissue. Chylomicrons are mainly composed of triglycerides (,85%) along with some cholesterol and cholesteryl esters. Apo B-48 is the main apolipoprotein content.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 56
Correct
-
Which of the following changes in the histology of the cell is most likely to be accompanied by disruption of the cell membrane following an injury?
Your Answer: Coagulative necrosis
Explanation:The process of necrosis ends with the rupture of the cell membrane and the consequent release of the cellular components into the surrounding tissue. Apoptosis, pyknosis and karyorrhexis are not reversible events but the cell membrane remains intact. Cloudy swelling and hydropic changes are also reversible but again the cell membrane remains intact and they are therefore different and distinct from necrosis.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 57
Incorrect
-
The blood-brain barrier is a membrane that separates the circulating blood from the brain extracellular fluid in the central nervous system (CNS). Which of the following statements regarding the blood– brain barrier is CORRECT?
Your Answer: It is more permeable in adults than in infants
Correct Answer: It breaks down in areas of brain that are infected
Explanation:The blood–brain barrier is a membrane that controls the passage of substances from the blood into the central nervous system. It is a physical barrier between the local blood vessels and most parts of the central nervous system and stops many substances from travelling across it. During meningitis, the blood–brain barrier may be disrupted. This disruption may increase the penetration of various substances (including either toxins or antibiotics) into the brain. A few regions in the brain, including the circumventricular organs, do not have a blood–brain barrier.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 58
Incorrect
-
During the fetal stage, the mesonephric tubules gives rise to the?
Your Answer: Vas deferens
Correct Answer: Wolffian duct
Explanation:The development of the kidney proceeds through a series of successive phases, each marked by the development of a more advanced kidney: the pronephros, mesonephros, and metanephros. The development of the pronephric duct proceeds in a cranial-to-caudal direction. As it elongates caudally, the pronephric duct induces nearby intermediate mesoderm in the thoracolumbar area to become epithelial tubules called mesonephric tubules. Each mesonephric tubule receives a blood supply from a branch of the aorta, ending in a capillary tuft analogous to the glomerulus of the definitive nephron. The mesonephric tubule forms a capsule around the capillary tuft, allowing for filtration of blood. This filtrate flows through the mesonephric tubule and is drained into the continuation of the pronephric duct, now called the mesonephric duct or Wolffian duct. The nephrotomes of the pronephros degenerate while the mesonephric duct extends towards the most caudal end of the embryo, ultimately attaching to the cloaca.
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This question is part of the following fields:
- Anatomy
- Embryology
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Question 59
Correct
-
When a young boy falls on his outstretched hand, he fractures one of the bones at his wrist joint. The doctors told his parents that the fractured bone has special importance as it is that bone that articulates with the distal end of the radius. Which one of the following is it?
Your Answer: Scaphoid
Explanation:It is the scaphoid bone that articulates with the radius at this level. It is located at the radial side of the wrist and is considered the largest bone in the proximal row of carpal bones. It articulates with the radius via its superior surface. This bone also articulates with trapezium and trapezoid bones via the inferior surface, capitate and lunate medially.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 60
Incorrect
-
A 65-year old patient with altered bowl movement experienced the worsening of shortness of breath and exertional chest pains over the course of 8 weeks. Examination shows pallor and jugular venous distension. Furthermore, a test of the stool for occult blood is positive. Laboratory studies show:
Haemoglobin 7.4 g/dl
Mean corpuscular volume 70 fl Leukocyte count 5400/mm3
Platelet count 580 000/mm3 Erythrocyte sedimentation 33 mm/h
A blood smear shows hypochromic, microcytic RBCs with moderate poikilocytosis. Which of the following is the most likely diagnosis?Your Answer: Anaemia of chronic disease
Correct Answer: Iron deficiency anaemia
Explanation:Iron deficiency anaemia is the most common type of anaemia. It can occur due to deficiency of iron due to decreased intake or due to faulty absorption. An MCV less than 80 will indicated iron deficiency anaemia. On the smear the RBC will be microcytic hypochromic and will also show piokilocytosis. iron profiles tests are important to make a diagnosis. Clinically the patient will be pale and lethargic.
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This question is part of the following fields:
- General
- Physiology
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Question 61
Incorrect
-
The gynaecologist suspects that her patient has a cervical cancer. What particular test should be done on this patient to screen for cervical cancer?
Your Answer: Ultrasound
Correct Answer: Pap smear
Explanation:Worldwide, approximately 500,000 new cases of cervical cancer and 274,000 deaths are attributable to cervical cancer yearly. This makes cervical cancer the second most common cause of death from cancer in women. The mainstay of cervical cancer screening has been the Papanicolaou test (Pap smear).
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 62
Incorrect
-
A 39-year old female patient was diagnosed with a tumour of the left adrenal gland. The tumour, which is metastasizing to the adjacent tissues, has already extended to the left suprarenal vein. If the tumour is still spreading, which of the following veins will most likely be affected after the involvement of the left suprarenal vein?
Your Answer: Inferior vena cava
Correct Answer: Left renal vein
Explanation:The suprarenal veins or also known as the veins of Warshaw, are the veins that receive blood from the suprarenal glands. These veins receive blood from the medullary venous plexus and the cortex of the adrenal glands (suprarenal glands). They are two in number – the left and the right suprarenal veins. The right suprarenal vein drains into the inferior vena cava while the left suprarenal vein drains into the left renal vein. This therefore means that in the case of a metastasizing tumour involving the left suprarenal vein, the tumour will most likely extend from the left suprarenal vein to the left renal vein into which it drains.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 63
Incorrect
-
An abnormal opening of the urethra on the under surface of the penis (ventral surface) is known as:
Your Answer: Epispadias
Correct Answer: Hypospadias
Explanation:Hypospadias is the condition where the urethra opens along the underside or ventral aspect of penile shaft. First-degree hypospadias is seen in 50-75% cases, where the urethra open on the glans penis. Second-degree hypospadias is seen in 20% cases where the urethra opens on the shaft, and third-degree in 30% cases with the urethra opening on the perineum. The severe cases are usually associated with undescended testis (cryptorchidism) or chordee, where the penis is tethered downwards and not completely separated from the perineum.
It is a common male genital birth defect but varying incidences are noted in different countries. There is no obvious inheritance pattern noted. No exact cause has been determined, however several hypotheses include poor response to androgen, or interference by environmental factors.
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This question is part of the following fields:
- Pathology
- Urology
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Question 64
Correct
-
Which of the following brings about a reduction in gastric blood flow?
Your Answer: Vasopressin
Explanation:Gastric blood flow is increased by vagal stimulation, gastrin, histamine and acetylcholine as they stimulate gastric section and the production of vasodilator metabolites. Acetylcholine and histamine also have a direct action on the gastric arterioles. Similarly, gastric blood flow is reduced by inhibitors of secretion – catecholamines, secretin and vasopressin.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 65
Incorrect
-
A 65-year-old man with no history of smoking complains of shortness of breath and persistent cough over the past 8 months. He reveals that in the 1960s he worked for several years as a boiler operator. Chest X-ray shows diffuse lung infiltrates. Which of the following is the most probable cause of these findings?
Your Answer: COPD
Correct Answer: Asbestosis
Explanation:Asbestosis is a chronic lung disease which leads to long-term respiratory complications and is caused by the inhalation of asbestos fibres. Symptoms due to long exposure to asbestos usually appear 10 to 40 years after initial exposure and include shortness of breath, cough, weight loss, clubbing of the fingers and chest pain. Typical chest X-ray findings include diffuse lung infiltrates that cause the appearance of shaggy heart borders.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 66
Incorrect
-
A young man was thrown from a vehicle in a collision. He landed on his head and shoulder tip, stretching the left side of his neck. A neurological examination revealed that the fifth and sixth cervical nerves had been torn from the spinal cord. What is the most obvious clinical manifestation of this?
Your Answer: Extension
Correct Answer: Abduction
Explanation:In the case of injuries to the upper roots of the brachial plexus there is complete loss of abduction. The muscle performing this movement is the supraspinatus. This initiates the movement, followed by the deltoid muscle, which allows for complete abduction. Both these muscles are innervated by nerves originating from C5 and C6. The injury to these roots results in a condition named Erb-Duchenne’s palsy.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 67
Incorrect
-
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: Right gastroepiploic
Correct 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.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 68
Incorrect
-
A chloride sweat test was performed on a 13-year-old boy. Results indicated a high likelihood of cystic fibrosis. This diagnosis is associated with a higher risk of developing which of the following?
Your Answer: Pneumocystis carinii pneumonia
Correct Answer: Bronchiectasis
Explanation:Cystic fibrosis is a life-threatening disorder that causes the build up of thick mucus in the lungs, digestive tract, and other areas of the body. It is a hereditary autosomal-recessive disease caused by mutations of the CFTR gene. Cystic fibrosis eventually results in bronchiectasis which is defined as a permanent dilatation and obstruction of bronchi or bronchioles.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 69
Correct
-
Which of the given options best describes the metabolic changes which occur following a severe soft tissue injury sustained after a PVA?
Your Answer: Mobilisation of fat stores
Explanation:The following metabolic responses occur following trauma as part of a coping mechanism for the additional stress. These include acid base changes (metabolic acidosis or alkalosis), decrease urine output and osmolality, reduced basal metabolic rate (BMR), gluconeogenesis with amino acid breakdown and shunting, hyponatraemia as a result of impaired functioning of sodium pumps, hypoxic injury, coagulopathies, decreased immunity, increase extracellular fluid and hypovolemic shock, increase permeability leading to oedema, break down and mobilization of fat reserves, pyrexia and reduced circulating levels of albumin.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 70
Incorrect
-
In a young, sexually active male, what is the most common cause of non-gonococcal urethritis?
Your Answer: Herpes simplex virus
Correct Answer: Chlamydia
Explanation:Non-gonococcal urethritis is most commonly caused by Chlamydia trachomatis (50% cases). Less common organisms include Mycoplasma genitalium, Urea urealyticum and Trichomonas vaginalis. Chlamydia is also the commonest cause of non-gonococcal cervicitis in women and proctitis in both sexes.
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This question is part of the following fields:
- Pathology
- Renal
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Question 71
Incorrect
-
If a 68-year-old man is diagnosed with a testicular seminoma that reaches the tunica albuginea and involves the tunica vaginalis, with retroperitoneal lymph nodes greater than 5cm, LDH 1.4 times the reference levels, β-hCG 4250 mIU/ml and AFP 780 ng/ml, what's the clinical stage in this case?
Your Answer: Stage IA
Correct Answer: Stage IIC
Explanation:According to the AJCC, the clinical staging for testicular seminoma is:
Stage IA: T1 N0 M0 S0
Stage IB: T2/3/4 N0 M0 S0
Stage IC: any T N0 M0 S1/2/3
Stage IIA: any T N1 M0 S0/1
Stage IIB: any T N2 M0 S0/1
Stage IIC: any T N3 M0 S0/1
Stage IIIA: any T any N M1a S0/1
Stage IIIB: any T any N M0/1a S2
Stage IIIC: any T any N M1a/1b S3.
The patient in this case has IIC stage -
This question is part of the following fields:
- Pathology
- Urology
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Question 72
Correct
-
What is the primary function of the Kupffer cells found in the liver?
Your Answer: Recycling of old red blood cells
Explanation:Kupffer cells found in the liver are part of the monocyte-reticular system. They are specialised macrophages and primarily function to recycle old and damaged RBCs. The RBCs are phagocytosed and the haemoglobin is broken down into haem and globin. The haem is further broken down into iron that is recycled and bilirubin that is conjugated with glucuronic acid and excreted in the bile.
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This question is part of the following fields:
- Inflammation & Immunology; Hepatobiliary
- Pathology
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Question 73
Incorrect
-
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: Polycythaemia vera
Correct 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.
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This question is part of the following fields:
- General
- Physiology
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Question 74
Incorrect
-
When inserting a chest drain anteriorly into the second intercostal space, one must identify the second costal cartilage by palpating which landmark?
Your Answer: Sternal notch
Correct Answer: Sternal angle
Explanation:The sternal angle is the site for identification of the second rib as the second rib is attached to the sternum at this point.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 75
Incorrect
-
Renin is secreted by pericytes in the vicinity of the afferent arterioles of the kidney from the juxtaglomerular cells. Plasma renin levels are decreased in patients with:
Your Answer: Renal artery stenosis
Correct Answer: Primary aldosteronism
Explanation:Primary aldosteronism, also known as primary hyperaldosteronism or Conn’s syndrome, is excess production of the hormone aldosterone by the adrenal glands resulting in low renin levels. Most patients with primary aldosteronism (Conn’s syndrome) have an adrenal adenoma. The increased plasma aldosterone concentration leads to increased renal Na+ reabsorption, which results in plasma volume expansion. The increase in plasma volume suppresses renin release from the juxtaglomerular apparatus and these patients usually have low plasma renin levels. Salt restriction and upright posture decrease renal perfusion pressure and therefore increases renin release from the juxtaglomerular apparatus. Secondary aldosteronism is due to elevated renin levels and may be caused by heart failure or renal artery stenosis.
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This question is part of the following fields:
- Physiology
- Renal
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Question 76
Correct
-
A 62-year-old man presented with a persistent cough and weight loss. Chest x-ray demonstrated widespread nodular opacities. After a bronchoalveolar lavage, atypical cells were detected. Which is the most probable diagnosis?
Your Answer: Bronchioalveolar carcinoma
Explanation:Bronchioloalveolar carcinoma (BAC) is a term used to define a particular subtype of adenocarcinoma which develops in cells near the alveoli, in the outer regions of the lungs. On a chest X-ray it can appear as a single peripheral spot or as scattered spots throughout the lungs. Symptoms include cough, haemoptysis, chest pain, dyspnoea and loss of weight.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 77
Incorrect
-
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: Pulmonary infarction
Correct 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.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 78
Incorrect
-
The majority of gallstones are mainly composed of:
Your Answer: Bile salts
Correct Answer: Cholesterol
Explanation:Bile salts are formed out of cholesterol in the liver cells. Occasionally, precipitation of cholesterol occurs resulting into cholesterol stones developing in the gall bladder.
These cholesterol gallstones are the most common type and account for 80% of all gallstones. Another type, accounting for 20% gallstones is pigment stones which are composed of bilirubin and calcium salts. Occasionally, stones of mixed origin are also seen.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 79
Incorrect
-
The primary motor cortex is located in the:
Your Answer: Cerebellar vermis
Correct Answer: Precentral gyrus
Explanation:The primary motor cortex is located in the dorsal part of the precentral gyrus and the anterior bank of the central sulcus. The precentral gyrus lies anterior to the postcentral gyrus and is separated from it by a central sulcus. Its anterior border is the precentral sulcus, while inferiorly it borders to the lateral fissure (Sylvian fissure).
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This question is part of the following fields:
- Neurology
- Physiology
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Question 80
Incorrect
-
Which of the following statements is true regarding the umbilical cord?
Your Answer: Is contained inside the body stalk
Correct Answer: Is filled with jelly of Wharton
Explanation:The umbilical cord that connects the fetus to the placenta is about 50cm long. This tissue consists of the body stalk and vitelline duct. The former containing the allantoic diverticulum and the umbilical vessels. The latter contains the connection linking the digestive tube and the yolk sac. This cord is wrapped by stratum of ectoderm and gelatinous tissue or jelly of Wharton. The right umbilical vein plus the vitelline vessels and ducts disappear and this at birth the cord has three vessels which are the umbilical vein and two umbilical arteries.
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This question is part of the following fields:
- Anatomy
- Embryology
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Question 81
Incorrect
-
A 79-year-old has been bedridden for 2 months after suffering from a stroke. She suddenly developed shortness of breath and chest pain, and was diagnosed with a pulmonary embolism. Which of the following is most likely to increase in this case?
Your Answer: Alveolar oxygen saturation
Correct Answer: Ventilation/perfusion ratio
Explanation:Pulmonary embolism (PE) is a blockage of an artery in the lungs by an embolus that has travelled from elsewhere in the body through the bloodstream. The change in cardiopulmonary function is proportional to the extent of the obstruction, which varies with the size and number of emboli obstructing the pulmonary arteries. The resulting physiological changes may include pulmonary hypertension with right ventricular failure and shock, dyspnoea with tachypnoea and hyperventilation, arterial hypoxaemia and pulmonary infarction. Consequent alveolar hyperventilation is manifested by a lowered pa(CO2). After occlusion of the pulmonary artery, areas of the lung are ventilated but not perfused, resulting in wasted ventilation with an increased ventilation/perfusion ratio – the physiological hallmark of PE – contributing to a further hyperventilatory state. The risk of blood clots is increased by cancer, prolonged bed rest, smoking, stroke, certain genetic conditions, oestrogen-based medication, pregnancy, obesity, and post surgery.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 82
Correct
-
If the blood flow is constant, oxygen extraction by tissues will show the greatest decrease due to which of the following interventions?
Your Answer: Tissue cooling
Explanation:With a constant blood flow to a given tissue bed, there will be an increase in oxygen extraction by the tissue with the following; an increase in tissue metabolism and oxygen requirements: warming (or fever), exercise, catecholamines and thyroxine. With cooling, the demand for oxygen decreases, leading to decreased oxygen extraction.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 83
Incorrect
-
A retroperitoneal structure is:
Your Answer: Sigmoid colon
Correct Answer: Pancreas
Explanation:Retroperitoneal structures are those that are found behind the peritoneum. They include: kidneys, suprarenal glands, bladder, ureter, inferior vena cava, rectum, oesophagus (part of it), part of the pancreas, 2nd, 3rd and 4th parts of the duodenum and ascending and descending parts of the colon.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 84
Incorrect
-
A 42 year old man presents with end stage renal failure and is prepared to receive a kidney from his best friend. HLA testing showed that they are not a 100% match and he is given immunosuppressant therapy for this. Three months later when his renal function is assessed, he showed signs of deteriorating renal function, with decreased renal output, proteinuria of +++ and RBCs in the urine. He was given antilymphocyte globulins and his condition reversed. During the crisis period the patient is likely to be suffering from?
Your Answer: Hyperacute rejection
Correct Answer: Acute rejection
Explanation:This patients is most likely experiencing an acute rejection. It is a cell mediated attack against the organ that has been transplanted. Antigens are either presented by blood borne cells with in the graft or antigen presenting cells in the body may be presenting class I and class II molecules that have been shed by the graft. Class I will activate CD8 and class II, CD4 cells, both of which will attack the graft.
Chronic rejection is a slow process which occurs months to years after the transplant. The exact mechanism is not very well understood but it probably involves a combination of Type III and Type IV hypersensitivity directed against the foreign MHC molecules which look like self-MHC presenting a foreign antigen.
Hyperacute Transplant Rejection occurs almost immediately and is often evident while you are still in surgery. It is caused by accidental ABO Blood type mismatching of the donor and recipient which almost never happens anymore. This means the host has preformed antibodies against the donated tissue.
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This question is part of the following fields:
- Inflammation & Immunology; Renal
- Pathology
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Question 85
Incorrect
-
A 50-year old gentleman who suffered a stroke was brought to the emergency department by his relatives. The patient however denied the presence of paralysis of his left upper and lower limbs. What is the most likely site of the lesion in this patient?
Your Answer: Right postcentral gyrus
Correct Answer: Right posterior parietal cortex
Explanation:A large injury to the non-dominant parietal cortex can make the patient neglect or refuse to acknowledge the presence of paralysis on the contralateral side. This can also involve the perception of the external world. Smaller injuries in this area which involve the precentral gyrus (primary motor cortex) or postcentral gyrus (primary sensory cortex) cause contralateral spastic paralysis or contralateral loss of tactile sensation respectively. A lesion in posterior inferior gyrus of the dominant frontal lobe results in motor aphasia. Involvement of the posterior superior gyrus of the dominant frontal lobe produces sensory aphasia.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 86
Incorrect
-
An amateur body-builder complains of increasing pain in his right shoulder after a few days of intense training. A surgeon aspirates clear fluid from his subdeltoid region. What's the most likely diagnosis?
Your Answer: Ganglion cyst
Correct Answer: Bursitis
Explanation:Bursae are potential cavities that contain synovial fluid, found in areas where friction occurs. Their function is to minimise friction and facilitate movement. Bursitis is the inflammation of one or more bursae, and they can occur in the shoulder, elbow, knee, ischium, amongst other joints. Acute bursitis can appear after strenuous exercise or activity, and chronic bursitis can develop following previous bursitis or trauma. Acute bursitis causes pain, tenderness, and swelling.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 87
Correct
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A 35 year old man presented to the surgical OPD with a lump on his right forearm which appeared 3 weeks ago and was tender on examination. He gave a history was being in a car accident with pieces of glass from the windshield piercing his forearm removed manually and on further elective surgery. Which of these cells are characteristically found during inflammation in this situation?
Your Answer: Giant cell
Explanation:A foreign body reaction Is characteristic of giant cells. Glass being the foreign object initiates an inflammatory response in this condition.
Mast cells are involved in allergic reactions.
Eosinophils are characteristic of a parasitic infection and allergic inflammatory process but are not due to foreign bodies.
Plasma cells are typical of chronic inflammation.
Lymphocytes are involved in viral infections.
Macrophages combine together to form giant cells.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 88
Incorrect
-
A teenage Somalian boy presents with a complaint of an enlarged lower jaw. His blood film shows blast cells and macrophages. Which virus is responsible for this?
Your Answer: Hepatitis C virus
Correct Answer: Epstein–Barr virus
Explanation:Burkitt’s lymphoma is a type of non-Hodgkin’s lymphoma. Histologically it is characterised by a starry sky appearance due to numerous neoplastic macrophages which are required to clear the rapidly dividing tumour cells/blast cells. Burkitt’s lymphoma commonly affects the jaw bone, forming a huge tumour mass. It is associated with translocation of c-myc gene and has three types: 1) endemic/African type, 2)sporadic and 3)immunodeficiency-associated. The first type is strongly associated with EBV.
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This question is part of the following fields:
- General
- Physiology
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Question 89
Correct
-
Which tumour occurs in young adults, affecting the epiphyses of the bones and sometimes extending to the soft tissues?
Your Answer: Benign giant-cell tumour
Explanation:Benign giant-cell tumours tend to affect adults in their twenties and thirties, occur in the epiphyses and can erode the bone and extend into the soft tissues. These tumours have a strong tendency to recur.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 90
Incorrect
-
Which of these HLA alleles is most likely to be present in ankylosing spondylitis?
Your Answer: HLA-B3
Correct Answer: HLA-B27
Explanation:Ankylosing spondylitis usually appears between the ages of 20-40 years old and is more frequent in men. It is strongly associated with HLA-B27, along with other spondyloarthropathies, which can be remembered through the mnemonic PAIR (Psoriasis, Ankylosing spondylitis, Inflammatory bowel disease, and Reactive arthritis).
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 91
Incorrect
-
The muscle that depresses the glenoid fossa directly is the:
Your Answer: Serratus anterior
Correct Answer: Pectoralis minor
Explanation:Situated at the upper part of the thorax beneath the pectoralis major, is a thin pectoralis minor, triangular muscle. It originates from the third, fourth and fifth ribs, near the cartilage and from the aponeurosis which covers the intercostals. These fibres move upwards and laterally to join and form a flat tendon. This is inserted into the medial border and upper surface of the coracoid process of the scapula. Through this medial anterior thoracic nerve, fibres from the pectoralis minor are received from the eighth cervical and first thoracic nerves. This pectoralis minor pushes down on the point of the shoulder (glenoid fossa), drawing the scapula downward and medially towards the thorax which throws the inferior angle backwards.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 92
Incorrect
-
A 32-year-old man presented with a metabolic acidosis and increased anion gap. What is the most likely cause of the changes of the anion gap in this patient?
Your Answer: Hyperviscosity
Correct Answer: Lactic acidosis
Explanation:High anion gap in metabolic acidosis is caused generally by the elevation of the levels of acids like ketones, lactate, sulphates in the body, which consume the bicarbonate ions. Other causes of a high anion gap include overdosing on salicylates, uraemia, rhabdomyolysis, hypocalcaemia, hypomagnesaemia, or ingestion of toxins such as ethylene glycol, methanol, propyl alcohol, cyanide and iron.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 93
Incorrect
-
Linezolid is an antibiotic used for the treatment of infections caused by bacteria that are resistant to other antibiotics. Which of the following organisms is most likely to be effectively treated by linezolid?
Your Answer: Entamoeba histolytica
Correct Answer: Methicillin-resistant Staphylococcus aureus
Explanation:Linezolid is a synthetic antibiotic used for the treatment of infections caused by multiresistant bacteria, including streptococci and methicillin-resistant Staphylococcus aureus (MRSA). Linezolid is effective against Gram-positive pathogens, notably Enterococcus faecium, S. aureus, Streptococcus agalactiae, Streptococcus pneumoniae and Streptococcus pyogenes. It has almost no effect on Gram-negative bacteria and is only bacteriostatic against most enterococci.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 94
Incorrect
-
A machine worker fractured the medial epicondyle of his right humerus resulting in damage to an artery running with the ulnar nerve posterior to the medial epicondyle. The artery injured is the?
Your Answer: Radial collateral
Correct Answer: Superior ulnar collateral
Explanation:The superior ulnar collateral artery runs posterior to the medial epicondyle of the humerus, accompanied by the ulnar nerve. This artery arises from the brachial artery near the middle of the arm and ends under the flexor carpi ulnaris muscle by anastomosing with two arteries: the posterior ulnar recurrent and inferior ulnar collateral.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 95
Incorrect
-
In the glomerulus of the kidney, the mesangium is a structure associated with the capillaries. It has extraglomerular mesangial cells that:
Your Answer: Provide structural support for and regulate blood flow of the glomerular capillaries by their contractile activity
Correct Answer: Form the juxtaglomerular apparatus in combination with the macula densa and juxtaglomerular cells
Explanation:The mesangium is an inner layer of the glomerulus, within the basement membrane surrounding the glomerular capillaries. The mesangial cells are phagocytic and secrete the amorphous basement membrane-like material known as the mesangial matrix. They are typically separated from the lumen of the capillaries by endothelial cells. The other type of cells in the mesangium are the extraglomerular mesangial cells which form the juxtaglomerular apparatus in combination with two other types of cells: the macula densa of the distal convoluted tubule and juxtaglomerular cells of the afferent arteriole. This apparatus controls blood pressure through the renin–angiotensin–aldosterone system.
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This question is part of the following fields:
- Physiology
- Renal
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Question 96
Incorrect
-
A 60-year-old woman complains of left sided headaches which have been recurring for several years. She recently suffered from a focal seizure for the first time a few days ago. A CT scan shows a mass in the left hemisphere of the brain. The most likely diagnosis is:
Your Answer: Glioblastoma multiforme
Correct Answer: Meningioma
Explanation:Meningiomas are a common benign intracranial tumour, and their incidence is higher in women between the ages of 40-60 years old. Many of these tumours are asymptomatic and are diagnosed incidentally, although some of them may have malignant presentations (less than 2% of cases). These benign tumours can develop wherever there is dura, over the convexities near the venous sinuses, along the base of the skull, in the posterior fossa and, within the ventricles.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 97
Incorrect
-
Which of the following diseases can cause paraesthesia along the distribution of the median nerve of the hand, especially after activities which require flexion and extension of the wrist?
Your Answer: Rheumatoid arthritis
Correct Answer: Carpal tunnel syndrome
Explanation:Carpal tunnel syndrome tends to occur in women between the ages of 30-50. There are many risk factors, including diabetes, hypothyroidism, obesity, pregnancy, and repetitive wrist work. Symptoms include pain in the hand and wrist, tingling, and numbness distributed along the median nerve (the palmar side of the thumb, the index and middle fingers, and the radial half of the ring finger), which worsens at night.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 98
Correct
-
A butcher accidentally cut himself on his right index finger. Which of the following substances when in contact with the basement membrane of the injured vasculature will activate the coagulation cascade as well as the kinin system in a first response to this injury?
Your Answer: Hageman factor
Explanation:Hageman factor/factor XII in the intrinsic pathway activates prekallikrein and factor XI. Deficiency will not cause excessive bleeding as other coagulation factors will be utilized but the PTT will be greater than 200 seconds.
Thromboxane promotes platelet aggregation and causes vasoconstriction.
Plasmin, which is cleaved from plasminogen acts as an anticoagulant which breaks down thrombi.
Platelet activating factor promotes platelet aggregation and is also chemotactic to neutrophils.
Histamine acts as a vasodilator.
Platelet inhibiting factor acts an anticoagulant.
Renin is a hormone released from the kidney that causes vasoconstriction and water retention.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 99
Incorrect
-
An 18 -year-old female is diagnosed with folliculitis in the left axilla. What is the most likely organism that could cause this condition?
Your Answer: Clostridium tetani
Correct Answer: Staphylococcus aureus
Explanation:Folliculitis is the inflammation of the hair follicles. It is usually caused by Staphylococcus infection.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 100
Incorrect
-
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: Hepatic
Correct Answer: Superior mesenteric
Explanation:The blood supply to the stomach is through the following arteries:
– The superior mesenteric artery supplies blood to the lower part of the duodenum, pancreas and two-thirds of the transverse colon. Thus ligation of the superior mesenteric artery would not affect the stomach.
– The right and the left gastroepiploic arteries supply the greater curvature of the stomach – along its edges.
– The short gastric artery supplies blood to the upper portion of the of the greater curvature and the fundus of the stomach.
– The gastroduodenal artery supplies blood to the distal part of the stomach (the pyloric sphincter) and the proximal end of the duodenum.
– The left gastroepiploic and the short gastric are branches of the splenic artery and therefore ligation of the splenic artery would directly affect the stomach.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 101
Incorrect
-
A 53 year old women with a history of atrial fibrillation developed an acute abdomen. On laparoscopic examination her bowels appeared to be dusky to red-purple in colour and her mesenteric veins appeared to be patent. Which of the following is most likely to occur in this situation?
Your Answer: Liquefactive gangrene
Correct Answer: Wet gangrene
Explanation:Infarction of the small bowel following a sudden and complete occlusion of the mesenteric artery can involve any portion of the bowel, whether small or a large. The splenic flexure is at most risk for infarction as it is the watershed area between the superior and inferior mesenteric vessels. Regardless of whether the arterial or the venous blood vessels are occluded, because of the blood reflow into the damaged portion, it will appear haemorrhagic. The bowel appearing congested at first and then becoming oedematous. If the artery is occluded then there will be a clear cut demarcation and in venous occlusion the dusky colour fades with the rest of the normal bowel. Wet gangrene is characteristic of ischaemic injury to the gut.
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This question is part of the following fields:
- Cell Injury & Wound Healing; Gastrointestinal
- Pathology
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Question 102
Incorrect
-
Prostatectomy carries a risk of loss of penile erection due to injury to the prostatic plexus responsible for an erection. From which nerves do these fibres originate?
Your Answer: Deep perineal
Correct Answer: Pelvic splanchnics
Explanation:Erection is a function of the parasympathetic nerves. Of the nerves listed, only the pelvic splanchnic nerves have parasympathetic fibres that innervate the smooth muscles and glands of the pelvic viscera.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 103
Correct
-
Decreased velocity of impulse conduction through the atrioventricular node (AV node) in the heart will lead to:
Your Answer: Increased PR interval
Explanation:AV node damage may lead to an increase in the PR interval to as high as 0.25 – 0.40 s (normal = 0.12 – 0.20 s). In the case of severe impairment, there might be a complete failure of passage of impulses leading to complete block. In this case, the atria and ventricles will beat independently of each other.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 104
Incorrect
-
Which of the following structures is derived from the dorsal mesogastrium of the stomach during the development of the gut?
Your Answer: Falciform ligament
Correct Answer: Greater omentum
Explanation:In a developing foetus, the stomach has two mesogastria from which most of the abdominal ligaments develop. These two mesogastria are the; ventral mesogastrium and the dorsal mesogastrium. During the embryological development of the gut, different organs develop in each mesogastrium; the spleen and pancreas in the dorsal mesogastrium while the liver in the ventral mesogastrium (with their associated ligaments). In the dorsal mesogastrium the following structures develop; the greater omentum (containing the gastrophrenic ligament and the gastrocolic ligament), gastrosplenic ligament, mesentery, splenorenal ligament and phrenicocolic ligament. The structures that develop from the ventral mesogastrium include the; lesser omentum (containing the hepatoduodenal ligament and the hepatogastric ligament) in association with the liver; the coronary ligament (left triangular ligament, right triangular ligament and hepatorenal ligament) and the falciform ligament (round ligament of liver and ligamentum venosum within).
There are also folds that develop from the dorsal mesogastrium which include; umbilical folds, supravesical fossa, medial inguinal fossa, lateral umbilical fold, lateral inguinal fossa and Ileocecal fold.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 105
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.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 106
Incorrect
-
A 50 year old man was admitted to the surgical ICU following a hemicolectomy for carcinoma of the caecum. A full blood count revealed: haematocrit = 30%, erythrocytes = 4 × 106/μ, haemoglobin level = 8 g/dl. To determine the likely cause of his anaemia, red blood cell indices were calculated. Which RBC indices are correct?
Your Answer: MCV = haematocrit × 1000/haemoglobin
Correct Answer: MCHC = haemoglobin concentration/haematocrit
Explanation:Mean corpuscular haemoglobin concentration (MCHC) is calculated simply by dividing the haemoglobin concentration (8 g/dl) by the haematocrit (0.3). The normal range is 31–36 g/dl. This patient has a hypochromic anaemia (MCHC = 8/0.3 = 26.7 g/dl). Dividing the haemoglobin concentration × 10 by erythrocyte number yields mean corpuscular haemoglobin (MCH). Normal range is 25.4–34.6 pg/cell and this patient has a significantly reduced cellular haemoglobin content (MCH = 8 × 10/4 = 20 pg/cell). Mean corpuscular volume (MCV) is calculated by dividing haematocrit × 1000 by erythrocyte number (4 × 106/μl). Normal range is 80–100 fl and this patient has a microcytic anaemia (MCV = 0.3 × 1000/4 = 75 fl). Microcytic, hypochromic anaemia is characteristic for iron-deficiency.
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This question is part of the following fields:
- General
- Physiology
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Question 107
Incorrect
-
A surgeon ligates the left superior suprarenal artery whilst preforming a left adrenalectomy. Where does the left superior suprarenal artery originate?
Your Answer: Renal artery
Correct Answer: Left inferior phrenic artery
Explanation:The superior suprarenal arteries arises from the inferior phrenic artery on either side.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 108
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.
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This question is part of the following fields:
- General
- Physiology
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Question 109
Incorrect
-
Which of the following associations is correctly matched with the body's defence mechanism in fighting infection?
Your Answer: First line of defence → neutrophils
Correct Answer: Specific cellular mechanism → cytotoxic T cells
Explanation:The immune system has certain levels of defence against pathogens. First line includes simple barriers such as skin, mucosa and stomach acid that prevent the pathogen from entering into the body. If this barrier is breached then the innate immune system is activated which includes leukocytes (macrophages, neutrophils, mast cells, eosinophils, basophils, natural killer cells). If the pathogens invade the second layer of defence then the third layer, adaptive immunity is activated, which includes B and T lymphocytes. B cells provide a humoral response whereas cytotoxic T cells have specific cellular mechanisms. They maintain a memory of past infections and are activated faster following a recurrence.
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This question is part of the following fields:
- General
- Physiology
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Question 110
Correct
-
Into which vein does the left and right inferior thyroid veins drain?
Your Answer: Brachiocephalic vein
Explanation:The brachiocephalic vein is formed by the confluence of the subclavian and internal jugular veins. In addition it receives drainage from: the left and right internal thoracic veins (also called internal mammary veins), left and right inferior thyroid veins and the left superior intercostal vein.
The superior thyroid veins and middle thyroid veins drain into the internal jugular vein. The right and left inferior thyroid veins to drain into their respective brachiocephalic veins (right and left). -
This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 111
Incorrect
-
A 45-year old farmer was referred to the surgical clinic with complaints of pain in his right hypochondrium. Investigations confirmed the diagnosis of hepatocellular carcinoma with malignant ascites. According to you, what is the most likely cause of HCC in this patient?
Your Answer: Hydrocarbons
Correct Answer: Aflatoxin
Explanation:Aflatoxins are naturally occurring toxins produced by the Aspergillus fungus (most often, A. flavus and A. parasiticus). These organisms are common and their native habitat is soil, decaying vegetation and grains. They can contaminate the grain before harvest or after storage, more likely in high-humidity (at least 7%) or high temperature environment of after stressful conditions like drought. Aflatoxins are mycotoxins and also carcinogenic. They get metabolized in the liver to an epoxide, aflatoxin M1. High exposure can lead to acute necrosis, cirrhosis or liver carcinoma. These substances can cause haemorrhage, acute liver damage, oedema, and alteration in digestion, absorption and/or metabolism of nutrients. Although humans are susceptible to these toxins like all other animals, they have a high tolerance level and hence, rarely develop acute aflatoxicosis. However, children are particularly susceptible to exposure leading to growth impairment and delayed development. Chronic exposure carries a high risk of hepatic cancer, due to intercalation of its metabolite aflatoxin M1 into the DNA and alkylation of the bases because of its epoxide moiety.
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 112
Correct
-
Carbon dioxide is principally transported in the blood in which form?
Your Answer: Bicarbonate
Explanation:Carbon dioxide is transported in the blood in various forms:
– Bicarbonate (80–90%)
– Carbamino compounds (5–10%)
– Physically dissolved in solution (5%).
Carbon dioxide is carried on the haemoglobin molecule as carbamino-haemoglobin; carboxyhaemoglobin is the combination of haemoglobin with carbon monoxide.
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This question is part of the following fields:
- Physiology
- Respiratory; Cardiovascular
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Question 113
Incorrect
-
A correct statement about the RECTUM:
Your Answer: It is surrounded by peritoneum along its entire length (about 12 cm long, normally)
Correct Answer: It is an important anastomotic site for the portal and caval (systemic) venous systems
Explanation:The rectum is part of the gastrointestinal tract that is continuous above with the sigmoid colon and below with the anal canal. It contains both longitudinal and circular smooth muscles. These are supplied by the enteric nervous system. It is about 12 cm long. It has no sacculations comparable with those of the colon. It has three permanent transverse folds called the valves of Houston. The peritoneum is related to the upper two thirds of the rectum only whereas the lower part is not covered by peritoneum. It is supplied by the superior rectal (hemorrhoidal) branch of the inferior mesenteric artery and the median sacral artery that is a direct branch from the abdominal aorta. It is drained by veins that begin as a plexus that surround the anus. These veins form anastomoses with the portal system (portocaval anastomoses).
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 114
Correct
-
When you rest your elbows on a desk, what bony landmark of the upper limb are you resting on?
Your Answer: Olecranon process of the ulna
Explanation:At the upper and back part of the ulna, there exists a curved eminence which is the olecranon process. This process lodges in the olecranon fossa of the humerus. It’s posterior surface is subcutaneous and this triangular area is what you rest your elbow upon.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 115
Incorrect
-
A man in his sixties underwent surgery to remove a lump from his axilla. During removal, a nerve originating from the lateral cord of the brachial plexus was damaged. Which nerve is this referring to?
Your Answer: Ulnar
Correct Answer: Lateral pectoral
Explanation:The only branch of the lateral cord of brachial plexus in the options given, is the lateral pectoral nerve. It supplies the pectoralis major muscle and sends a branch to join the medial pectoral nerve forming a loop in front of the first part of the axillary artery.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 116
Incorrect
-
A neonate with failure to pass meconium is being evaluated. His abdomen is distended and X-ray films of the abdomen show markedly dilated small bowel and colon loops. The likely diagnosis is:
Your Answer: Meckel’s diverticulum
Correct Answer: Aganglionosis in the rectum
Explanation:Hirschsprung’s disease (also known as aganglionic megacolon) leads to colon enlargement due to bowel obstruction by an aganglionic section of bowel that starts at the anus. A blockage is created by a lack of ganglion cells needed for peristalsis that move the stool. 1 in 5000 children suffer from this disease, with boys affected four times more commonly than girls. It develops in the fetus in early stages of pregnancy. Symptoms include not having a first bowel movement (meconium) within 48 hours of birth, repeated vomiting and a swollen abdomen. Two-third of cases are diagnosed within 3 months of birth. Some children may present with delayed toilet training and some might not show symptoms till early childhood. Diagnosis is by barium enema and rectal biopsy (showing lack of ganglion cells).
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 117
Incorrect
-
An explorative laparotomy is done on a 23 year old following a gunshot abdominal injury through the right iliac fossa. It is found that the ileocolic artery is severed and the bullet had perforated the caecum. From which branch does the ileocolic artery originate?
Your Answer: Hepatic artery
Correct Answer: Superior mesenteric artery
Explanation:Ileocolic artery branches off from the superior mesenteric artery. It then divides to give a superior and inferior branch.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 118
Incorrect
-
A 68-year-old woman complains of headaches, dizziness, and memory loss. About a month ago, she fell from a staircase but only suffered mild head trauma. What is the most likely diagnosis in this case?
Your Answer: Intracerebral haematoma
Correct Answer: Chronic subdural haematoma
Explanation:A quarter to a half of patients with chronic subdural haematoma have no identifiable history of head trauma. If a patient does have a history of head trauma, it usually is mild. The average time between head trauma and chronic subdural haematoma diagnosis is 4–5 weeks. Symptoms include decreased level of consciousness, balance problems, cognitive dysfunction and memory loss, motor deficit (e.g. hemiparesis), headache or aphasia. Some patients present acutely. They usually result from tears in bridging veins which cross the subdural space, and may cause an increase in intracranial pressure (ICP).
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This question is part of the following fields:
- Neurology
- Pathology
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Question 119
Incorrect
-
A elderly patient with bulbar palsy is bed ridden. While swallowing he aspirates one of his tablets into his lungs. In which bronchopulmonary segments is it most likely to end up?
Your Answer:
Correct Answer: Superior segmental bronchus of the right inferior lobe
Explanation:Inhaled objects are more likely to enter the right lung for several reasons. First the right bronchus is shorter, wider and more vertical than the left bronchus. Also, the carina (a ridge-like structure at the point of tracheal bifurcation) is set a little towards the left. The superior segmental bronchus branches posteriorly off the intermediate bronchus or the inferior lobe bronchus and is thus more likely to receive the foreign body that enters the right main bronchus. The lingula is only found on the left lung. The terminal bronchiole is a very small space almost impossible for the tablet to lodge here.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 120
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:
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.
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This question is part of the following fields:
- Haematology
- Pathology
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