-
Question 1
Correct
-
A 13-year-old girl has complained of pain in her left arm for 4 months. An X-ray reveals a mass along with erosion of the affected humerus. Histologically, the tumour is found to be formed by small, round, blue cells. What is the most likely diagnosis?
Your Answer: Ewing’s sarcoma
Explanation:Ewing’s sarcoma is formed by small, round, blue cells, and is common in children. The usually develop in limbs, and clinical findings include pain and inflammation, with lytic destruction showing up on X-rays.
-
This question is part of the following fields:
- Orthopaedics
- Pathology
-
-
Question 2
Correct
-
Leukotrienes normally function during an asthma attack and work to sustain inflammation. Which of the following enzymes would inhibit their synthesis?
Your Answer: 5-lipoxygenase
Explanation:Leukotrienes are produced from arachidonic acid with the help of the enzyme 5-lipoxygenase. This takes place in the eosinophils, mast cells, neutrophils, monocytes and basophils. They are eicosanoid lipid mediators and take part in allergic and asthmatic attacks. They are both autocrine as well as paracrine signalling molecules to regulate the body’s response and include: LTA4, LTB4, LTC4, LTD4, LTE4 and LTF4.
-
This question is part of the following fields:
- Inflammation & Immunology
- Pathology
-
-
Question 3
Incorrect
-
Injury to which of the following arteries is likely to affect the blood supply to the seminal vesicles?
Your Answer: Superior vesical
Correct Answer: Middle rectal
Explanation:Ligation of middle rectal artery is most likely to affect the blood supply of seminal vesicles since arteries supplying the seminal vesicles are derived from the middle and inferior vesical and middle rectal arteries.
-
This question is part of the following fields:
- Anatomy
- Pelvis
-
-
Question 4
Incorrect
-
A 50-year-old man is diagnosed with emphysema and cirrhosis of the liver. Which of the following condition may be the cause of both cirrhosis and emphysema in this patient?
Your Answer: Cystic fibrosis
Correct Answer: Alpha1-antitrypsin deficiency
Explanation:Alpha-1 antitrypsin (A1AT) deficiency is a condition characterised by the lack of a protein that protects the lungs and liver from damage, called alpha1-antytripsin. The main complications of this condition are liver diseases such as cirrhosis and chronic hepatitis, due to accumulation of abnormal alpha 1-antytripsin and emphysema due to loss of the proteolytic protection of the lungs.
-
This question is part of the following fields:
- Pathology
- Respiratory
-
-
Question 5
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.
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 6
Correct
-
With respect to far accommodation, which of the following is a TRUE statement?
Your Answer: The ciliary muscles are relaxed
Explanation:Myopia or near-sightedness is a disease due to elongated eyeballs or too strong a lens. For far accommodation (focus of a distant object onto the retina), the lens needs to decrease its refractive power, or in other words, increase its focal length. This is done by relaxation of ciliary muscles which tightens the zonular fibres and flattening of the lens. Relaxation of the zonular fibres, rounding of the lens, shortening of the focal length and constriction of the pupil occurs during near accommodation.
-
This question is part of the following fields:
- Neurology
- Physiology
-
-
Question 7
Incorrect
-
Which best describes the sartorius muscle?
Your Answer: Is innervated by the same nerve as the tensor fascia lata
Correct Answer: Will flex the leg at the knee joint
Explanation:The sartorius muscle arises from tendinous fibres from the superior iliac spine. It passes obliquely across the thigh from lateral to medial and is inserted into the upper part of the medial side of the tibia. When the sartorius muscle contracts it will flex the leg at the knee joint.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 8
Incorrect
-
A significantly elevated white cell count of 50 x 109/l with 5% blasts and raised leucocyte alkaline phosphatase is seen in which of the following conditions?
Your Answer:
Correct Answer: Leukaemoid reaction
Explanation:Non-neoplastic proliferation of leucocytes causes an increase in leukocyte alkaline phosphatase (LAP). This is referred to as ‘leukemoid reaction’ because of the similarity to leukaemia with an increased white cell count (>50 × 109/l) with immature forms. Causes of leukemoid reaction includes haemorrhage, drugs (glucocorticoids, all-trans retinoic acid etc), infections such as tuberculosis and pertussis, and as a paraneoplastic phenomenon. Leukemoid reaction can also be seen in infancy as a feature of trisomy 21. This is usually a benign condition, but can be a response to a disease state. Differential diagnosis include chronic myelogenous leukaemia (CML).
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 9
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:
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
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 10
Incorrect
-
Which of the following toxins most likely results in continuous cAMP production, which pumps H2O, sodium, potassium, chloride and bicarbonate into the lumen of the small intestine and results in rapid dehydration?
Your Answer:
Correct Answer: Cholera toxin
Explanation:The cholera toxin (CTX or CT) is an oligomeric complex made up of six protein subunits: a single copy of the A subunit (part A), and five copies of the B subunit (part B), connected by a disulphide bond. The five B subunits form a five-membered ring that binds to GM1 gangliosides on the surface of the intestinal epithelium cells. The A1 portion of the A subunit is an enzyme that ADP-ribosylates G proteins, while the A2 chain fits into the central pore of the B subunit ring. Upon binding, the complex is taken into the cell via receptor-mediated endocytosis. Once inside the cell, the disulphide bond is reduced, and the A1 subunit is freed to bind with a human partner protein called ADP-ribosylation factor 6 (Arf6). Binding exposes its active site, allowing it to permanently ribosylate the Gs alpha subunit of the heterotrimeric G protein. This results in constitutive cAMP production, which in turn leads to secretion of H2O, Na+, K+, Cl−, and HCO3− into the lumen of the small intestine and rapid dehydration. The gene encoding the cholera toxin was introduced into V. cholerae by horizontal gene transfer.
-
This question is part of the following fields:
- Microbiology
- Pathology
-
-
Question 11
Incorrect
-
An 18 year-old with an iron deficient diet was prescribed an iron supplement by her GP. Lack of iron often results in:
Your Answer:
Correct Answer: Hypochromic anaemia
Explanation:Iron deficiency anaemia is the most common type of anaemia. It can occur due to deficiency of iron from decreased intake, increased loss or inadequate absorption. An MCV less than 80 will indicated iron deficiency anaemia. On the smear the RBCs will be microcytic hypochromic and will also show poikilocytosis. Iron profile tests are important to make a diagnosis. Clinically the patient will be pale and lethargic.
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 12
Incorrect
-
A 55- year old male patient with cancer of the head of the pancreas was to undergo whipple's operation to have the tumour removed. During the surgery, the surgeon had to ligate the inferior pancreaticoduodenal artery to stop blood supply to the head of the pancreas. Which of the following arteries does the inferior pancreaticoduodenal artery branch from?
Your Answer:
Correct Answer: Superior mesenteric artery
Explanation:The inferior pancreaticoduodenal artery is a branch of the superior mesenteric artery or from the first intestinal branch of the superior mesenteric artery. Once given off, it runs to the right between the pancreatic head and the duodenum and then ascends to form an anastomosis with the superior pancreaticoduodenal artery.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 13
Incorrect
-
During a normal respiratory exhalation, what is the recoil alveolar pressure?
Your Answer:
Correct Answer: +10 cmH2O
Explanation:To determine compliance of the respiratory system, changes in transmural pressures (in and out) immediately across the lung or chest cage (or both) are measured simultaneously with changes in lung or thoracic cavity volume. Changes in lung or thoracic cage volume are determined using a spirometer with transmural pressures measured by pressure transducers. For the lung alone, transmural pressure is calculated as the difference between alveolar (pA; inside) and intrapleural (ppl; outside) pressure. To calculate chest cage compliance, transmural pressure is ppl (inside) minus atmospheric pressure (pB; outside). For the combined lung–chest cage, transmural pressure or transpulmonary pressure is computed as pA – pB. pA pressure is determined by having the subject deeply inhale a measured volume of air from a spirometer. Under physiological conditions the transpulmonary or recoil pressure is always positive; intrapleural pressure is always negative and relatively large, while alveolar pressure moves from slightly negative to slightly positive as a person breathes.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 14
Incorrect
-
A 47 -year-old male was admitted due to a bleeding peptic ulcer. On his 3rd hospital day, he developed a cardiac arrhythmia. His serum potassium was markedly elevated. What is the most likely cause of hyperkalaemia in this patient?
Your Answer:
Correct Answer: Multiple blood transfusions
Explanation:Patients with gastrointestinal bleeding often require blood transfusion. Among the various side effects of blood transfusions, is the increase of potassium levels. The use of stored blood for transfusions is followed by an increase of serum potassium levels. Potassium level increases are more pronounced in patients who receive blood stored for more than 12 d. Furthermore, the lysis and destruction of red blood cells, especially in the transfusion of older PRBCs, can further increase potassium levels. Excessive use of a PPi has been associated with hyperkaelemia however would be less likely in this acute setting.
-
This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
-
-
Question 15
Incorrect
-
An 80 year-old quadriplegic man has been lying supine for 7 weeks in a critical care ward. He develops a right lung abscess that is draining by gravity to a particular region of the lung. Which is the most likely site of pus collection?
Your Answer:
Correct Answer: Superior segment of the lower lobe
Explanation:The superior segmental bronchus of the lower lobe of the right lung branches posteriorly off the intermediate bronchus or the inferior lobe bronchus. It is therefore more likely to receive fluid or foreign bodies that enter the right main bronchus especially when the patient is supine.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 16
Incorrect
-
Which muscle originates from the common flexor tendon of the forearm?
Your Answer:
Correct Answer: Flexor digitorum superficialis
Explanation:The medial epicondyle of the humerus is the site of origin of this group of muscles of the forearm. It originates from the medial epicondyle of the humerus by a common tendon. Fibres from the deep fascia of the forearm, near the elbow and septa, pass from this fascia between the muscles. These muscles include the pronator teres, palmaris longus, flexor carpi radialis, flexor carpi ulnaris and flexor digitorum superficialis.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 17
Incorrect
-
A 24 year old mother is breastfeeding her first child. Which of the following cellular adaptations occurred in her breast tissue to allow her to do this?
Your Answer:
Correct Answer: Lobular hyperplasia
Explanation:Under the influence of oestrogen in pregnancy, there is an increase in the number of lobules which will facilitate lactation.
Steatocytes occur due to loss of weight and nutritional deficit.
Metaplasia is a normal physiological process which is due to a change in normal epithelium with another type.
Lobular atrophy will result in a decreased capacity to provide milk.
-
This question is part of the following fields:
- Cell Injury & Wound Healing; Female Health
- Pathology
-
-
Question 18
Incorrect
-
A glycogen storage disorder is characterised by increased liver glycogen with a normal structure and no increase in serum glucose after oral intake of a protein-rich diet. Deficiency of which of the following enzymes is responsible for this disorder?
Your Answer:
Correct Answer: Glucose-6-phosphatase
Explanation:The most common glycogen storage disorder is von Gierke’s disease or glycogen storage disease type I. It results from a deficiency of enzyme glucose-6-phosphatase which affects the ability of liver to produce free glucose from glycogen and gluconeogenesis; leading to severe hypoglycaemia. There is also increased glycogen storage in the liver and kidneys causing enlargement and various problems in their functioning. The disease also causes lactic acidosis and hyperlipidaemia. The main treatment includes frequent or continuous feedings of corn-starch or other carbohydrates.
-
This question is part of the following fields:
- Gastroenterology
- Physiology
-
-
Question 19
Incorrect
-
Which of the following veins is prostate cancer most likely to metastasize through?
Your Answer:
Correct Answer: Internal vertebral venous plexus
Explanation:The internal vertebral veins are the most likely route of metastasis as they are valveless. They serve an important clinical role as they are the route of free travel for cancerous cells to other body structures. The other veins on the list have valves and would be the least likely routes for metastasis.
-
This question is part of the following fields:
- Anatomy
- Neurology
-
-
Question 20
Incorrect
-
A 43-year-old diabetic man complains of headaches, palpitations, anxiety, abdominal pain and weakness. He is administered sodium bicarbonate used to treat:
Your Answer:
Correct Answer: Metabolic acidosis
Explanation:Sodium bicarbonate is indicated in the management of metabolic acidosis, which may occur in severe renal disease, uncontrolled diabetes, circulatory insufficiency due to shock or severe dehydration, extracorporeal circulation of blood, cardiac arrest and severe primary lactic acidosis. Bicarbonate is given at 50-100 mmol at a time under scrupulous monitoring of the arterial blood gas readings. This intervention, however, has some serious complications including lactic acidosis, and in those cases, should be used with great care.
-
This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
-
-
Question 21
Incorrect
-
A 57-year-old male smoker noted a lump on his inner lip. Upon physical examination the lump measured more than 2 cm but less than 4 cm in its greatest dimension. He is diagnosed with squamous cell carcinoma of the lip. What is the stage of the patient's cancer according to the TNM staging for head and neck cancers?
Your Answer:
Correct Answer: T2
Explanation:Head and neck cancer is a group of cancers that starts within the mouth, nose, throat, larynx, sinuses, or salivary glands. The TNM staging system used for head and neck cancers is a clinical staging system that allows physicians to compare results across patients, assess prognosis, and design appropriate treatment regimens. The staging is as follows; Primary tumour (T): Tis: pre-invasive cancer (carcinoma in situ), T0: no evidence of primary tumour, T1: tumour 2 cm or less in its greatest dimension, T2: tumour more than 2 cm but not more than 4 cm, T3: tumour larger than 4 cm, T4: tumour with extension to bone, muscle, skin, antrum, neck, etc and TX: minimum requirements to assess primary tumour cannot be met. Regional lymph node involvement (N): N0: no evidence of regional lymph node involvement, N1: evidence of involvement of movable homolateral regional lymph nodes, N2: evidence of involvement of movable contralateral or bilateral regional lymph nodes, N3: evidence of involvement of fixed regional lymph nodes and NX: Minimum requirements to assess the regional nodes cannot be met. Distant metastases (M): M0: no evidence of distant metastases, M1: evidence of distant metastases and MX: minimum requirements to assess the presence of distant metastases cannot be met. Staging: Stage I: T1 N0 M0, Stage II: T2 N0 M0, Stage III: T2NOMO and T3N1MO, Stage IV: T4N1M0, any TN2M0, any TN3M0, any T and any NM1. The depth of infiltration is predictive of the prognosis. With increasing depth of invasion of the primary tumour, the risk of nodal metastasis increases and survival decreases. The patient in this scenario therefore has a T2 tumour.
-
This question is part of the following fields:
- Neoplasia
- Pathology
-
-
Question 22
Incorrect
-
A 34-year-old woman is diagnosed with cerebral oedema after suffering a severe head trauma. Which of the following conditions is not likely to be associated with the extracellular oedema?
Your Answer:
Correct Answer: Increased plasma colloid osmotic pressure
Explanation:Cerebral oedema is extracellular fluid accumulation in the brain. Increased capillary permeability, increased capillary pressure, increased interstitial fluid colloid osmotic pressure and lymphatic blockage would increase fluid movement into the interstitial spaces. Increased plasma colloid osmotic pressure, however, would oppose fluid movement from the capillaries into the interstitial compartment.
-
This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
-
-
Question 23
Incorrect
-
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:
Correct 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.
-
This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
-
-
Question 24
Incorrect
-
What Is the mechanism behind rhesus incompatibility in a new born baby?
Your Answer:
Correct Answer: Type II hypersensitivity
Explanation:In type II hypersensitivity the antibodies that are produced by the immune response bind to the patients own cell surface antigens. These antigens can be intrinsic or extrinsic. Destruction occurs due to antibody dependent cell mediated antibodies. Antibodies bind to the cell and opsonise the cell, activating phagocytes to destroy that cell e.g. autoimmune haemolytic anaemia, Goodpasture syndrome, erythroblastosis fetalis, pernicious anaemia, Graves’ disease, Myasthenia gravis and haemolytic disease of the new-born.
-
This question is part of the following fields:
- Inflammation & Immunology; Haematology
- Pathology
-
-
Question 25
Incorrect
-
A 45-year old with sarcoidosis has enlarged tracheobronchial lymph nodes. Which nerve is most likely to be irritated in this patient?
Your Answer:
Correct Answer: Left recurrent laryngeal
Explanation:Tracheobronchial lymph nodes are located at the bifurcation of the trachea and are in three groups i.e. the right superior, left superior and inferior. The aorta arches over the left bronchus near the point of tracheal bifurcation. Thus, the nerves that are closely associated with the aorta might be irritated if these nodes become inflamed. The left recurrent laryngeal nerve is such a nerve. The phrenic nerves, both the left and the right, are lateral and thus would not be affected. The right recurrent nerve loops around the right subclavian artery and is distant from this area. The right vagus artery is not associated with the aorta and the sympathetic chain is located in the posterior chest parallel to the vertebra, also not associated with the tracheobronchial tree.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 26
Incorrect
-
A 36-year-old woman suddenly suffers from a generalized seizure. She was previously healthy. An emergency CT scan reveals a mass in the posterior fossa, with distortion of the lateral ventricles. After removing the tumour, the biopsy reveals it contains glial fibrillary acidic protein (GEAP). What's the most likely diagnosis?
Your Answer:
Correct Answer: Astrocytoma
Explanation:Astrocytomas are primary intracranial tumours derived from astrocyte cells of the brain. They can arise in the cerebral hemispheres, in the posterior fossa, in the optic nerve and, rarely, in the spinal cord. These tumours express glial fibrillary acidic protein (GFAP). In almost half of cases, the first symptom of an astrocytoma is the onset of a focal or generalised seizure. Between 60% and 75% of patients will have recurrent seizures during the course of their illness. Secondary clinical sequelae may be caused by elevated intracranial pressure (ICP) cause by the direct mass effect, increased blood volume, or increased cerebrospinal fluid (CSF) volume. CT will usually show distortion of the third and lateral ventricles, with displacement of the anterior and middle cerebral arteries. Histological diagnosis with tissue biopsy will normally reveal an infiltrative character suggestive of the slow growing nature of the tumour.
-
This question is part of the following fields:
- Neurology
- Pathology
-
-
Question 27
Incorrect
-
A 24-year old patient diagnosed with a direct inguinal hernia was scheduled for surgery to have the hernia repaired. The hernia was discovered to be protruding through the Hesselbach's triangle (inguinal triangle). Which of the following blood vessels that is a branch of the external iliac artery forms the lateral border of this triangle?
Your Answer:
Correct Answer: Inferior epigastric
Explanation:The inguinal triangle is formed by the following structures; inguinal ligament at the base; inferior epigastric vessels laterally and the lateral border of the rectus sheath medially. This triangle (also known as Hesselebach’s triangle) is where direct inguinal hernias protrude. The inferior epigastric artery is this the branch of the external iliac artery being referred to. All the other blood vessels are branches of the internal iliac artery.
-
This question is part of the following fields:
- Anatomy
- Pelvis
-
-
Question 28
Incorrect
-
Which one of the following is a derivative of the midgut?
Your Answer:
Correct 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.
-
This question is part of the following fields:
- Anatomy
- Embryology
-
-
Question 29
Incorrect
-
Different substances have different renal clearance rates. Which of the following substances should have the lowest renal clearance rate in a healthy patient?
Your Answer:
Correct Answer: Glucose
Explanation:Under normal conditions the renal clearance of glucose is zero, since glucose is completely reabsorbed in the renal tubules and not excreted. Glycosuria – the excretion of glucose into the urine- is nearly always caused by elevated blood glucose levels, most commonly due to untreated diabetes mellitus.
-
This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
-
-
Question 30
Incorrect
-
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:
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.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 31
Incorrect
-
An X ray of a 60 year old male brought to the accident and emergency following a fall down stairs shows a fractured olecranon process of the right ulna with the line of fracture passing through the superior surface, disrupting a muscle. Which among the following muscles was most likely injured?
Your Answer:
Correct Answer: Triceps brachii
Explanation:The superior surface of the olecranon process forms an attachment for the insertion of the triceps brachii on the posterior aspect. It also has a minor transverse groove for the attachment of part of the posterior ligament of the elbow on the anterior aspect.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 32
Incorrect
-
A chest x ray is ordered for a 39 year old man who presents with a history of a cough and weight loss for over a month. It shows a rounded opacity in the pleural cavity near the cardiac notch. The opacity is most likely to be in the:
Your Answer:
Correct Answer: Costomediastinal recess
Explanation:The costomediastinal recess is the point where the costal pleura becomes the mediastinal pleura, located right next to the cardiac notch.
The cupola: part of the parietal pleura that extends above the first rib to the root of the lung.
Hilum: located on the medial surface of the lung where neurovascular structures enter and leave the lung.
Pulmonary ligament: pleural fold found below the root of the lung, is a point of continuity between the visceral and mediastinal pleura.
Costodiaphragmatic recess: the lowest extent of the pleural cavity.
Superior mediastinum: part of the mediastinum that contains the great vessels leaving and entering the heart.
The cardiac notch is in the inferior mediastinum.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 33
Incorrect
-
The circle of Willis is an arterial anastomosis in the base of the brain and is one of the cerebrovascular safeguards in the brain. Where is the circle of Willis contained?
Your Answer:
Correct Answer: Cisterna basalis
Explanation:Cisterns refers to a system of intercommunicating pools formed by the subarachnoid space at the base of the brain and around the brainstem. Cisterna basalis/basal cistern (interpeduncular cistern) is found at the base of the brain between the two temporal lobes and it contains the arterial circle of Willis. The lumbar cistern is contained in the spinal canal while the foramen magna refers to the opening at the base of the skull though which the spinal cord enters into the skull.
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 34
Incorrect
-
A 55-year old lady underwent a major surgery for repair of an aortic aneurysm. Her blood pressure was low throughout the intra-operative and the post-operative period, along with increasing serum creatinine and urea. Microscopic examination of her urine showed multiple granular and hyaline casts. What is the likely condition the patient is suffering from?
Your Answer:
Correct Answer: Acute tubular necrosis
Explanation:The most common predisposing factor leading to acute tubular necrosis is ischemia, typically seen in hospitalized patients with low blood pressure.
-
This question is part of the following fields:
- Pathology
- Renal
-
-
Question 35
Incorrect
-
Which of the following is true about myasthenia gravis?
Your Answer:
Correct Answer: Response of skeletal muscle to nerve stimulation is weakened
Explanation:An autoimmune disorder, myasthenia gravis leads to progressive muscle weakness. It occurs due to formation of antibodies against the nicotinic acetylcholine (ACh) receptor of the motor endplate, which leads to impaired neuromuscular transmission. Thus, nerve stimulation will lead to a weakened muscle response, but direct electrical stimulation will bring about a normal response. Diagnostic test includes improvement of muscle weakness by small doses of acetylcholinesterase inhibitors (physostigmine or edrophonium). However, a large dose of physostigmine worsens the weakness due to desensitisation of the endplate to persistent Ach. One of the investigative tools includes radiolabelled snake venom α-bungarotoxin. It is an in vitro study performed on muscle biopsy specimens and used to quantify the number of ACh receptors at the motor endplate.
-
This question is part of the following fields:
- Neurology
- Physiology
-
-
Question 36
Incorrect
-
Which is the most common benign germ-cell tumour that could occur in a premenopausal woman?
Your Answer:
Correct Answer: Dermoid cyst
Explanation:A dermoid cyst is a teratoma of a cystic nature that contains an array of developmentally mature and solid tissues. Dermoid cysts grow slowly and this type of cystic teratoma is nearly always benign.
-
This question is part of the following fields:
- Neoplasia
- Pathology
-
-
Question 37
Incorrect
-
Which best describes the suprascapular nerve?
Your Answer:
Correct Answer: It contains nerve fibres from C5 and C6 spinal cord segments
Explanation:The suprascapular nerve arises from the cervical spinal nerves 5 and 6 after coming together to form common trunk. This nerve supplies the supraspinatus and infraspinatus muscles giving off branches to the shoulder joint.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 38
Incorrect
-
A patient with chronic renal disease, missed a day of his dialysis schedule., His serum potassium was 7.6 mmol/L when his electrolytes were checked. What is the ECG finding expected in this patient?
Your Answer:
Correct Answer: Tented T waves
Explanation:ECG characteristics of hyperkalaemia may show the following changes: P-waves are widened and of low amplitude due to slowing of conduction, widened QRS complex, QRS-T fusion, loss of ST segment and tall tented T waves.
-
This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
-
-
Question 39
Incorrect
-
A retroperitoneal structure is:
Your Answer:
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.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 40
Incorrect
-
A 30-year-old woman feels thirsty. This thirst is probably due to:
Your Answer:
Correct Answer: Increased level of angiotensin II
Explanation:Thirst is the basic need or instinct to drink. It arises from a lack of fluids and/or an increase in the concentration of certain osmolites such as salt. If the water volume of the body falls below a certain threshold or the osmolite concentration becomes too high, the brain signals thirst. Excessive thirst, known as polydipsia, along with excessive urination, known as polyuria, may be an indication of diabetes. Angiotensin II is a hormone that is a powerful dipsogen (i.e. it stimulates thirst) that acts via the subfornical organ. It increases secretion of ADH in the posterior pituitary and secretion of ACTH in the anterior pituitary.
-
This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
-
-
Question 41
Incorrect
-
Which is a feature of the action of insulin?
Your Answer:
Correct Answer: Promotes protein synthesis
Explanation:Insulin is produced by the beta-cells of the islets of Langerhans in the pancreas. Its actions include:
– promoting uptake of glucose into cells
– glycogen synthesis (glycogenesis)
– protein synthesis
– stimulation of lipogenesis (fat formation).
– driving potassium into cells – used to treat hyperkaelamia.
Parathyroid hormone and activated vitamin D are the principal hormones involved in calcium/phosphate metabolism, rather than insulin.
-
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 42
Incorrect
-
In a study, breast lumps were analysed to determine the characteristic of malignant neoplasm on biopsy. What microscopic findings are suggestive of malignancy?
Your Answer:
Correct Answer: Invasion
Explanation:Invasion is suggestive of malignancy and an even better option would have been metastasis. Pleomorphism is found in both benign and malignant neoplasms along with atypia and anaplasia. A height nuclear/cytoplasmic ratio is suggestive of malignancy but not the best indicator. Malignant tumours are aggressive and growth rapidly. Necrosis can be seen in benign tumours if they deplete their blood supply.
-
This question is part of the following fields:
- Neoplasia
- Pathology
-
-
Question 43
Incorrect
-
A 35-year-old ultra marathon runner becomes severely dehydrated and collapses. This patient most likely has:
Your Answer:
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.
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 44
Incorrect
-
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:
Correct 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.
-
This question is part of the following fields:
- Orthopaedics
- Pathology
-
-
Question 45
Incorrect
-
A 76 year old man who presented with lower back pain is diagnosed with prostatic carcinoma that has metastasized to his lumber spine. Which of the following markers is characteristically elevated?
Your Answer:
Correct Answer: PSA
Explanation:Spread of prostatic carcinoma is common to the lumbar spine and pelvis. This results in osteoblastic metastases that will present as lower back pain with increased alkaline phosphatase, prostatic acid phosphates and PSA. PSA is more specific and a PSA > 10 ng/ml for any age is worrisome.
-
This question is part of the following fields:
- Neoplasia; Urology
- Pathology
-
-
Question 46
Incorrect
-
Which of the following structures carry part of the right bundle branch of the AV bundle?
Your Answer:
Correct Answer: Moderator band (septomarginal trabecula)
Explanation:The moderator band extends from the base of the anterior papillary muscle to the ventricular septum. It is the structure which carries part of the right AV bundle. Its role it to prevent overdistention of the ventricle.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 47
Incorrect
-
A 34-year-old woman with pelvic inflammatory disease is administered ceftriaxone. The subclass of antibiotics that ceftriaxone belongs to is:
Your Answer:
Correct Answer: Third-generation cephalosporins
Explanation:Ceftriaxone is a third-generation cephalosporin antibiotic. It has a broad spectrum of activity against Gram-positive and Gram-negative bacteria. Its indications include middle ear infections, endocarditis, meningitis, pneumonia, bone and joint infections, intra-abdominal infections, skin infections, urinary tract infections, gonorrhoea, and pelvic inflammatory disease.
-
This question is part of the following fields:
- Pathology
- Pharmacology
-
-
Question 48
Incorrect
-
Signals pass through neuromuscular junctions via the neurotransmitter acetylcholine. After release from the skeletal neuromuscular junction, acetylcholine:
Your Answer:
Correct Answer: Causes postsynaptic depolarisation
Explanation:Acetylcholine is released from the presynaptic membrane into the cleft where it binds to the ion gated channels on the post synaptic membrane, causing them to open. This results in sodium entering into the fibre and further depolarizing it, creating an action potential.
-
This question is part of the following fields:
- General
- Physiology
-
-
Question 49
Incorrect
-
Which of the following muscle divide the posterior triangle of the neck into the occipital and the subclavian triangle?
Your Answer:
Correct Answer: Inferior belly of the omohyoid
Explanation:The posterior triangle (or lateral cervical region) is a region of the neck bounded in front by the sternocleidomastoid; behind, by the anterior margin of the trapezius; inferiorly by the middle third of the clavicle and superiorly by the occipital bone. The posterior triangle is crossed, about 2.5 cm above the clavicle, by the inferior belly of the omohyoid muscle, which divides the space into two triangles: an upper or occipital triangle and a lower or subclavian triangle (or supraclavicular triangle).
-
This question is part of the following fields:
- Anatomy
- Head & Neck
-
-
Question 50
Incorrect
-
A 69 Year old lady presented to the emergency department following a massive myocardial infarction. She was found to be in hypotensive shock with focal neurological signs. Unfortunately the patient demised. What would be the expected findings on the brain biopsy?
Your Answer:
Correct Answer: Liquefactive necrosis
Explanation:Liquefactive necrosis is often associated with bacterial or fungal infections. However, hypoxic death of cells within the central nervous system can also result in liquefactive necrosis. The focal area is soft with a liquefied centre containing necrotic debris and dead white cells. This may later be enclosed by a cystic wall
-
This question is part of the following fields:
- Cell Injury & Wound Healing; Neurology
- Pathology
-
00
Correct
00
Incorrect
00
:
00
:
0
00
Session Time
00
:
00
Average Question Time (
Mins)