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  • Question 1 - Gram positive bacteria differ from gram negative bacteria due to the presence of...

    Correct

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

      Your Answer: Outer membrane

      Explanation:

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

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      14.7
      Seconds
  • Question 2 - During an exploratory laparotomy a herniation of bowel is identified between the lateral...

    Correct

    • During an exploratory laparotomy a herniation of bowel is identified between the lateral edge of the rectus abdominis, the inguinal ligament and the inferior epigastric vessels. These boundaries define the hernia as being a:

      Your Answer: Direct inguinal hernia

      Explanation:

      The boundaries given define the inguinal triangle which is the site for direct inguinal hernias. Indirect inguinal hernias occur lateral to the inferior epigastric vessels.

      Femoral hernias protrude through the femoral ring, into the femoral canal.

      Umbilical hernias protrude through a defect in the umbilical area.

      Obturator hernias, occur through the obturator foramen. These are very rare.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      16.7
      Seconds
  • Question 3 - Where is the foramen ovale located? ...

    Correct

    • Where is the foramen ovale located?

      Your Answer: Sphenoid

      Explanation:

      The foramen ovale is an oval shaped opening in the middle cranial fossa located at the posterior base of the greater wing of the sphenoid bone, lateral to the lingula. It transmits the mandibular division of the trigeminal nerve (CN Vc), accessory meningeal artery, emissary veins between the cavernous sinuses and pterygoid plexus, otic ganglion, and occasionally the nervus spinosus and lesser petrosal nerve.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      17.8
      Seconds
  • Question 4 - A 15-year-old girl was diagnosed with bacterial meningitis. Gram staining of the spinal...

    Correct

    • A 15-year-old girl was diagnosed with bacterial meningitis. Gram staining of the spinal fluid shows numerous polymorphonuclear neutrophils and Gram-positive cocci. Which is the empiric drug of choice to be given to the patient until the antibiotic sensitivity report is available?

      Your Answer: Ceftriaxone

      Explanation:

      Acute meningitis is a medical emergency. All suspects should receive their first dose of antibiotics immediately and be transferred to hospital as soon as possible. If facilities for blood culture and/or lumbar puncture (LP) are immediately available, they should be performed before administration
      of the first dose of antibiotics (see contraindications to LP below). Neither procedure should lead to a significant delay in antibiotic administration.
      Administer ceftriaxone 80-100 mg/kg (maximum 2 g, 12 hourly) intravenously. The intramuscular or intraosseous route can be used if there is no vascular access. Penicillin allergy is not a contraindication to ceftriaxone in acute meningitis (C-1). Omit ceftriaxone only if there has been documented ceftriaxone anaphylaxis. Give chloramphenicol 25 mg/kg (maximum 500 mg) intravenously instead, if available. Administer adequate analgesia and transfer the patient immediately to hospital, detailing all administered
      medication in the referral letter.

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      26.6
      Seconds
  • Question 5 - Which of the following diseases causes abrupt vertigo, nausea, vomiting, tinnitus, and nystagmus?...

    Correct

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

      Your Answer: Vestibular neuronitis

      Explanation:

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

    • This question is part of the following fields:

      • Neurology
      • Pathology
      9.9
      Seconds
  • Question 6 - Regarding the extensor retinaculum of the wrist, which of these is CORRECT? ...

    Correct

    • Regarding the extensor retinaculum of the wrist, which of these is CORRECT?

      Your Answer: It prevents the tendons of the posterior compartment of the forearm from ‘bowstringing’ when the hand is extended at the wrist

      Explanation:

      This extensor retinaculum, as the name indicates, holds the tendons of the extensors against the dorsal surface of the distal radius and ulna. Therefore, the correct answer is that it prevents bowstringing of the extensor tendons with wrist extension. It forms compartments between it and its bony attachment, and these compartments guide and hold the tendons.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      15.8
      Seconds
  • Question 7 - A 40-year old man sustained a deep laceration to the sole of his...

    Incorrect

    • A 40-year old man sustained a deep laceration to the sole of his left foot. It was found that the belly of extensor digitorum muscle was lacerated and the lateral tarsal artery was severed. The lateral tarsal artery is a branch of the:

      Your Answer: Posterior tibial artery

      Correct Answer: Dorsalis pedis artery

      Explanation:

      The lateral tarsal artery arises from the dorsalis pedis, as the vessel crosses the navicular bone

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      26.8
      Seconds
  • Question 8 - A 20-year old involved in a brawl was stabbed in the anterior chest...

    Correct

    • A 20-year old involved in a brawl was stabbed in the anterior chest in a structure that is in close proximity to where the first rib articulates with the sternum. What is the structure that was most likely injured?

      Your Answer: Sternoclavicular joint

      Explanation:

      The first rib articulates with the sternum right below the sternoclavicular joint.

      The sternal angle articulates with the costal cartilage of the second rib.

      The nipple is found between the fourth and the fifth ribs, in the fourth intercostal space.

      The xiphoid process is located right below the point of articulation of the costal cartilage of rib 7 with the sternum.

      The root of the lung is the part of the lung where neurovascular structures enter and leave the lung.

      Acromioclavicular joint is the point of articulation between the acromion process and the clavicle, near the shoulder.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      34
      Seconds
  • Question 9 - During a procedure to treat an ulcer in the first part of the...

    Correct

    • During a procedure to treat an ulcer in the first part of the duodenum, the most appropriate site to make the incision on the anterior abdominal wall to approach this ulcer would be the:

      Your Answer: Epigastric region

      Explanation:

      The abdomen is divided into nine regions for descriptive purposes. The epigastric region contains the first part of the duodenum, part of the stomach, part of the liver and pancreas. This would be the region that the surgeon would need to enter to access the ulcer.

      Typically, a midline incision in the epigastric region, extending from just below the xiphoid process down to the umbilicus, provides excellent access to the first part of the duodenum.

      The left inguinal region contains the sigmoid colon.

      The left lumbar region contains the descending colon and kidney.

      The right lumbar region contains the right kidney and descending colon.

      The right hypochondrial region contains part of the liver and gall bladder.

      The hypogastric region contains the urinary bladder and the rectum.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      10.2
      Seconds
  • Question 10 - Which is the site of action of the drug omeprazole? ...

    Incorrect

    • Which is the site of action of the drug omeprazole?

      Your Answer: Passive diffusion of H+

      Correct Answer: H+/K+ ATPase

      Explanation:

      H+/K+-ATPase or ‘proton pump’ located in the canalicular membrane plays a major role in acid secretion. The ATPase here is magnesium-dependent. Omeprazole is a proton pump inhibitor and blocks H+/K+- ATPase.

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      11.6
      Seconds
  • Question 11 - Calculate the stroke volume in a patient admitted for coronary bypass surgery, with...

    Correct

    • Calculate the stroke volume in a patient admitted for coronary bypass surgery, with the following parameters pre-operatively:

      Oxygen consumption = 300 ml/min

      Arterial oxygen content = 20 ml/100 ml blood

      Pulmonary arterial oxygen content = 15 ml/100 ml blood and Heart rate = 100 beats/min.

      Your Answer: 60 ml

      Explanation:

      By Fick’s principle, cardiac output can be calculated as follows: VO2 = CO × (CAO2– CVO2) where VO2= oxygen consumption, CO = cardiac output, CAO2 = arterial oxygen content and CvO2 = mixed venous oxygen content. Thus, in the given problem, 300 ml/min = CO × (20 – 15) ml/100 ml CO = 300 × 100/5 ml/min CO = 6000 ml/min. Also, cardiac output = stroke volume × heart rate. Thus, 6000 ml/min = stroke volume × 100 beats/min. Hence, stroke volume = 6000/100 ml/min which is 60 ml/min.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      26.7
      Seconds
  • Question 12 - Nephrotic syndrome is a condition that causes proteinuria, hypoalbuminemia and oedema. Which of...

    Correct

    • Nephrotic syndrome is a condition that causes proteinuria, hypoalbuminemia and oedema. Which of the following is the cause of the oedema in these patients?

      Your Answer: Decreased oncotic pressure

      Explanation:

      The glomeruli of the kidneys are the parts that normally filter the blood. They consist of capillaries that are fenestrated and allow fluid, salts and other small solutes to flow through, but normally not proteins. In nephrotic syndrome, the glomeruli become damaged allowing small proteins, such as albumin to pass through the kidneys into urine. Oedema usually occurs due to salt and water retention by the diseased kidneys as well as due to the reduced colloid oncotic pressure (because of reduced albumin in the plasma). Lower serum oncotic pressure causes fluid to accumulate in the interstitial tissues.

    • This question is part of the following fields:

      • Physiology
      • Renal
      4.7
      Seconds
  • Question 13 - A surgeon ligates the left middle suprarenal artery while carrying out a left...

    Correct

    • A surgeon ligates the left middle suprarenal artery while carrying out a left adrenalectomy. Where does the left middle suprarenal artery originate?

      Your Answer: Abdominal aorta

      Explanation:

      Middle suprarenal arteries arise from either side of the abdominal aorta, opposite the superior mesenteric artery.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      25.1
      Seconds
  • Question 14 - Which of these substances is secreted by pericytes in the juxtaglomerular cells? ...

    Correct

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

      Your Answer: Renin

      Explanation:

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

    • This question is part of the following fields:

      • Physiology
      • Renal
      4.4
      Seconds
  • Question 15 - A patient in the intensive care unit developed hyperphosphatemia. The phosphate level is...

    Correct

    • A patient in the intensive care unit developed hyperphosphatemia. The phosphate level is 160 mmol/L. Which of the following is most likely responsible for this abnormality?

      Your Answer: Renal insufficiency

      Explanation:

      Hyperphosphatemia is an electrolyte disturbance in which there is an abnormally elevated level of phosphate in the blood. It is caused by conditions that impair renal phosphate excretion (ex: renal insufficiency, hypoparathyroidism, parathyroid suppression) and conditions with massive extracellular fluid phosphate loads (ex: rapid administration of exogenous phosphate, extensive cellular injury or necrosis, transcellular phosphate shifts).

    • This question is part of the following fields:

      • Fluids & Electrolytes
      • Pathology
      14.6
      Seconds
  • Question 16 - What Is the mechanism behind rhesus incompatibility in a new born baby? ...

    Incorrect

    • What Is the mechanism behind rhesus incompatibility in a new born baby?

      Your Answer: Type III hypersensitivity

      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
      6.3
      Seconds
  • Question 17 - A 75-year old patient is in atrial fibrallation but has never been on...

    Correct

    • A 75-year old patient is in atrial fibrallation but has never been on anticoagulation therapy. To reduce the risk of future emboli, she would benefit from starting on long-term warfarin. Arterial emboli leading to acute limb ischaemia most commonly lodge at which one of the following sites?

      Your Answer: Common femoral artery

      Explanation:

      The common femoral artery is the commonest site of arterial emboli causing acute limb ischemia. The treatment of choice is urgent femoral embolectomy.

    • This question is part of the following fields:

      • Cardiovascular
      • Pathology
      32.4
      Seconds
  • Question 18 - Which of the following is a fact worth noting about the development of...

    Incorrect

    • Which of the following is a fact worth noting about the development of the spleen?

      Your Answer: It becomes retroperitoneal during its development

      Correct Answer: It develops in the dorsal mesogastrium

      Explanation:

      The spleen in the human embryo arises in week 5 of intrauterine life. It appears as a proliferating mesenchyme above the pancreas. The spleen is one the organs that develops in the dorsal mesogastrium. When the stomach changes its position during development, the spleen is made to move behind the stomach and stays in contact with the left kidney. The spleen is found within the peritoneum of the abdominal cavity thus it is an intraperitoneal organ.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      40.9
      Seconds
  • Question 19 - A 20 year old is brought to the A&E after he fell from...

    Correct

    • A 20 year old is brought to the A&E after he fell from a moving cart. The boy has sustained blunt abdominal injury, and the there is a possibility of internal bleeding as the boy is in shock. An urgent exploratory laparotomy is done in the A&E theatre. On opening the peritoneal cavity, the operating surgeon notices a torn gastrosplenic ligament with a large clot around the spleen. Which artery is most likely to have been injured in this case?

      Your Answer: Short gastric

      Explanation:

      The short gastric arteries branch from the splenic artery near the splenic hilum to travel back in the gastrosplenic ligament to supply the fundus of the stomach. Therefore, these may be injured in this case.

      The splenic artery courses deep to the stomach to reach the hilum of the spleen. It doesn’t travel in the gastrosplenic ligament although it does give off branches that do.

      The middle colic artery is a branch of the superior mesenteric artery that supplies the transverse colon.

      Gastroepiploic artery is the largest branch of the splenic artery that courses between the layers of the greater omentum to anastomose with the right gastroepiploic.

      Left gastric artery, a branch of the coeliac trunk. It supplies the left half of the lesser curvature.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      12
      Seconds
  • Question 20 - A 29-year-old woman presents to the doctor complaining of cough, shortness of breath,...

    Incorrect

    • A 29-year-old woman presents to the doctor complaining of cough, shortness of breath, fever and weight loss. Chest X-ray revealed bilateral hilar and mediastinal lymph node enlargement and bilateral pulmonary opacities. Non-caseating granulomas were found on histological examination. The most likely diagnosis is:

      Your Answer: Tuberculosis

      Correct Answer: Sarcoidosis

      Explanation:

      Sarcoidosis is an inflammatory disease of unknown aetiology that affects multiple organs but predominantly the lungs and intrathoracic lymph nodes. Systemic and pulmonary symptoms may both be present. Pulmonary involvement is confirmed by a chest X-ray and other imaging studies. The main histological finding is the presence of non-caseating granulomas.

    • This question is part of the following fields:

      • Pathology
      • Respiratory
      20.3
      Seconds
  • Question 21 - A 10-year-old boy was sent for an x-ray of the leg because he...

    Incorrect

    • A 10-year-old boy was sent for an x-ray of the leg because he was complaining of pain and swelling. The x-ray showed the classic sign of Codman's triangle. What is the most likely diagnosis of this patient?

      Your Answer: Aneurysmal bone cyst

      Correct Answer: Osteosarcoma

      Explanation:

      Codman’s triangle is the triangular area of new subperiosteal bone that is created when a lesion, often a tumour, raises the periosteum away from the bone. The main causes for this sign are osteosarcoma, Ewing’s sarcoma, eumycetoma, and a subperiosteal abscess.

    • This question is part of the following fields:

      • Neoplasia
      • Pathology
      32.5
      Seconds
  • Question 22 - Where does the ejaculatory duct open into? ...

    Correct

    • Where does the ejaculatory duct open into?

      Your Answer: Prostatic urethra

      Explanation:

      There are two ejaculatory ducts, one on either side of the midline. Each ejaculatory duct is formed by the union of the duct from the seminal vesicles with the ductus deferens. They start at the base of the prostate and run forward and downward between the middle and lateral lobes and along the side of the prostatic utricle to end in the prostatic urethra.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      12.7
      Seconds
  • Question 23 - A 40 year old woman, who is under anaesthesia for an elective procedure,...

    Incorrect

    • A 40 year old woman, who is under anaesthesia for an elective procedure, received an antibiotic injection. She immediately developed a rash and her airway constricted raising the airway pressure. Which mechanism is responsible for this reaction?

      Your Answer: Type II hypersensitivity

      Correct Answer: Type I hypersensitivity

      Explanation:

      Type I hypersensitivity reaction is an immediate reaction that occurs due to binding of the antigen with antibodies attached to mast cells in a previously sensitized person. It has an immediate phase, which is characterised by vasodilation, leakage of plasma, smooth muscle spasm, or glandular secretions. This manifests in about 5-30 min and usually resolves within 60 mins. The delayed phase follows after 24 hours and can persist up to several days. It is due to infiltration of eosinophils, neutrophils, basophils and CD4+ cells and leads to tissue destruction. The nature of the reaction varies according to the site. It can take the form of skin allergy, hives, allergic rhinitis, conjunctivitis, bronchial asthma or food allergy.

    • This question is part of the following fields:

      • Inflammation & Immunology
      • Pathology
      10.2
      Seconds
  • Question 24 - A 77-year-old woman's renal function is tested. The following results were obtained during...

    Incorrect

    • A 77-year-old woman's renal function is tested. The following results were obtained during a 24-h period:

      Urine flow rate: 2. 0 ml/min

      Urine inulin: 0.5 mg/ml

      Plasma inulin: 0.02 mg/ml

      Urine urea: 220 mmol/l

      Plasma urea: 5 mmol/l.

      What is the urea clearance?

      Your Answer: 320 ml/min

      Correct Answer: 88 ml/min

      Explanation:

      Urea is reabsorbed in the inner medullary collecting ducts of the nephrons. The clearance (C) of any substance can be calculated as follows: C = (U × V)/P, where U and P are the urine and plasma concentrations of the substance, respectively and V is the urine flow rate. So, glomerular filtration rate = (0.220 × 2. 0)/0.005 = 88 ml/min.

    • This question is part of the following fields:

      • Fluids & Electrolytes
      • Physiology
      68.7
      Seconds
  • Question 25 - Which of these nerves controls adduction of hand? ...

    Correct

    • Which of these nerves controls adduction of hand?

      Your Answer: Ulnar nerve

      Explanation:

      The adductors of the fingers are the palmer interossei. They are supplied by the ulnar nerve, which is a branch of the medical cord of the brachial plexus.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      12.6
      Seconds
  • Question 26 - Which of the following is the most common germ cell tumour of the...

    Correct

    • Which of the following is the most common germ cell tumour of the testis affecting an adult male?

      Your Answer: Seminoma

      Explanation:

      Germ cell tumours represent 90% of primary tumours arising in the testis. They are broadly divided into seminomas and non-seminomas. Seminomas are the most common testicular germ cell tumour seen in 40% cases. The other non-seminomatous histological subtypes include embryonal (25%), teratocarcinoma (25%), teratoma (5%) and pure choriocarcinoma (1%).

    • This question is part of the following fields:

      • Pathology
      • Urology
      16.2
      Seconds
  • Question 27 - Which of the following mediators of inflammation requires arachidonic acid for synthesis? ...

    Correct

    • Which of the following mediators of inflammation requires arachidonic acid for synthesis?

      Your Answer: Prostaglandins

      Explanation:

      Arachidonic acid is normally present in the phospholipids that make up the cell membrane and is cleaved by phospholipase A2 from the phospholipid. Arachidonic acid is a precursor for the production of eicosanoids which include: 1) prostaglandins, prostacyclins and thromboxane, 2) leukotrienes and 3) anandamides. The production of these products along with their action on the body is called the arachidonic acid cascade.

    • This question is part of the following fields:

      • Inflammation & Immunology
      • Pathology
      7
      Seconds
  • Question 28 - Which is the most common benign germ-cell tumour that could occur in a...

    Incorrect

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

      Your Answer: Myoma

      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
      20.7
      Seconds
  • Question 29 - What is the chief ligament preventing posterior sliding of the tibia on the...

    Correct

    • 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.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      7.6
      Seconds
  • Question 30 - Which of the following will be a seen in a patient with a...

    Correct

    • Which of the following will be a seen in a patient with a plasma thyroid-stimulating hormone (TSH) level of 14 mU/l (normal < 5 mU/l) and a low T3 resin uptake of 19% (normal 25–35%)?

      Your Answer: Periorbital swelling and lethargy

      Explanation:

      Low T3 resin uptake combined with raised TSH is indicative of hypothyroidism. Signs and symptoms include dull expression, facial puffiness, lethargy, periorbital swelling due to infiltration with mucopolysaccharides, bradycardia and cold intolerance. Anxiety, palpitations, tachycardia, raised body temperature, heat intolerance and weight loss are all seen in hyperthyroidism.

    • This question is part of the following fields:

      • Endocrinology
      • Physiology
      8.7
      Seconds
  • Question 31 - A 55-year-old woman complains of pain in the proximal and distal interphalangeal joins,...

    Correct

    • A 55-year-old woman complains of pain in the proximal and distal interphalangeal joins, and back pain which has increased over the last 4 years and worsens after activity. X-rays reveal Heberden’s and Bouchard’s nodes in her interphalangeal joints and the presence of osteophytes in her spine. What is the most likely diagnosis?

      Your Answer: Osteoarthritis

      Explanation:

      Osteoarthritis is most common in older adults, predominating in women between the ages of 40 and 70; after this age, men and women are affected equally. It affects an entire joint, with disruption and potential loss of joint cartilage, along with other joint changes, including bone hypertrophy (osteophyte formation). The pain is usually gradual and is worse after activity, with occasional joint swelling. X-ray findings include marginal osteophytes, narrowing of the joint space, increased density of the subchondral bone, subchondral cyst formation, bony remodelling and joint effusions.

    • This question is part of the following fields:

      • Orthopaedics
      • Pathology
      30.3
      Seconds
  • Question 32 - What is the normal amount of oxygen that is carried in the blood?...

    Correct

    • What is the normal amount of oxygen that is carried in the blood?

      Your Answer: 20 ml oxygen/100 ml blood

      Explanation:

      Normally, 100 ml of blood contains 15g haemoglobin and a single gram of haemoglobin can bind to 1.34 ml oxygen when 100% saturated. Thus, 15 × 1.34 = 20 ml O2/100 ml blood. The haemoglobin in venous blood that is leaving the tissues is about 75% saturated with oxygen, and hence it carries about 15 ml O2/100 ml venous blood. This implies that for each 10 ml of blood, 5 ml oxygen is transported to the tissues. With a p(O2) > 100 mm Hg, only 3 ml of oxygen is dissolved in every one litre of plasma. By increasing the pA(O2) by breathing 100% oxygen, one can add an extra amount of oxygen in the plasma, but the amount of oxygen carried by haemoglobin will not increase significantly as it is already > 95% saturated.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      2.8
      Seconds
  • Question 33 - Which is the CORRECT statement regarding the small intestine: ...

    Correct

    • Which is the CORRECT statement regarding the small intestine:

      Your Answer: The superior mesenteric artery courses between the body and uncinate process of the pancreas before the artery supplies the jejunum and ileum

      Explanation:

      The small intestine extends from the pylorus to the ileocecal valve where It ends in the large intestine. It is surrounded on the sides and above by the large intestine. It is related anteriorly with the greater omentum and abdominal wall. Is connected to the vertebral column by a fold of peritoneum or otherwise known as the mesentery. Is divided into three portions: the duodenum, jejunum and ileum. The jejunum and ileum are supplied by the superior mesenteric artery that courses between the body and uncinate process of the pancreas before it gives off intestinal branches.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      31.3
      Seconds
  • Question 34 - Whipple's procedure involves mobilizing the head of the pancreas. As the surgeon does...

    Incorrect

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

      Your Answer: Gastroduodenal artery

      Correct Answer: Common bile duct

      Explanation:

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

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      14.9
      Seconds
  • Question 35 - In the case of an injury to the sub sartorial canal, which of...

    Incorrect

    • In the case of an injury to the sub sartorial canal, which of the following structures is most likely to be injured?

      Your Answer: Nerve to sartorius

      Correct Answer: Nerve to vastus medialis

      Explanation:

      The adductor canal (sub sartorial canal) is situated in the middle third of the thigh.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      28
      Seconds
  • Question 36 - What is expected from complete transection of the inferior gluteal nerve when it...

    Correct

    • What is expected from complete transection of the inferior gluteal nerve when it emerges from the greater sciatic foramen?

      Your Answer: Extension of the thigh would be the action most affected

      Explanation:

      As the inferior gluteal nerve emerges from the greater sciatic foramen below the piriformis muscle, it divides into branches and enters the gluteus maximus muscle which extends the femur and bends the thigh in line with the body.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      32.6
      Seconds
  • Question 37 - The sciatic nerve does NOT supply which of the following muscles? ...

    Incorrect

    • The sciatic nerve does NOT supply which of the following muscles?

      Your Answer: Biceps femoris

      Correct Answer: Obturator externus

      Explanation:

      The sciatic nerve supplies both gemellae, quadratus femoris, semitendinosus, semimembranosus, both heads of the biceps femoris, the hamstring half of abductor magnus and obturator internus. Obturator externus is supplied by the obturator nerve.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      14.3
      Seconds
  • Question 38 - The superior rectal artery is a continuation of the: ...

    Correct

    • The superior rectal artery is a continuation of the:

      Your Answer: Inferior mesenteric artery

      Explanation:

      The superior rectal artery or superior haemorrhoidal artery is the continuation of the inferior mesenteric artery. It descends into the pelvis between the layers of the mesentery of the sigmoid colon, crossing the left common iliac artery and vein.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      18.5
      Seconds
  • Question 39 - Multiple, non-tender lymphadenopathy with biopsy showing several crowded follicles of small, monomorphic lymphocytes...

    Correct

    • Multiple, non-tender lymphadenopathy with biopsy showing several crowded follicles of small, monomorphic lymphocytes and the absence of Reed-Sternberg cells is seen in which of the following?

      Your Answer: Poorly differentiated lymphocytic lymphoma

      Explanation:

      Malignant lymphoma usually causes non-tender lymphadenopathy, unlike the tender lymphadenopathy caused by infections (including infectious mononucleosis caused by Epstein-Barr virus). Also, the lymphoid hyperplasia seen in infectious mononucleosis is benign and polyclonal.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      13
      Seconds
  • Question 40 - Which of the following cytokines produced by the T cell induce MHC-II proteins?...

    Incorrect

    • Which of the following cytokines produced by the T cell induce MHC-II proteins?

      Your Answer: Tumour necrosis factor

      Correct Answer: γ-Interferon

      Explanation:

      Interferons elicit a non-specific antiviral activity by inducing specific RNA synthesis and expression of proteins in neighbouring cells. Common interferon inducers are viruses, double-stranded RNA and micro-organisms. INF-γ is produced mainly by CD4+, CD8+ T cells and less commonly by B cells and natural killer cells. INF-γ has antiviral and antiparasitic activity but its main biological activity appears to be immunomodulatory. Among its many functions are activation of macrophages and enhanced expression of MHC-II proteins or macrophages.

    • This question is part of the following fields:

      • General
      • Physiology
      15.5
      Seconds
  • Question 41 - The Brunner glands secrete an alkaline product that helps maintain an optimal pH...

    Correct

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

      Your Answer: Submucosa of the duodeneum

      Explanation:

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

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      11.1
      Seconds
  • Question 42 - After finding elevated PSA levels, a 69-year-old man undergoes a needle biopsy and...

    Incorrect

    • After finding elevated PSA levels, a 69-year-old man undergoes a needle biopsy and is diagnosed with prostatic cancer. What is the stage of this primary tumour?

      Your Answer: T2b

      Correct Answer: T1c

      Explanation:

      The AJCC uses a TNM system to stage prostatic cancer, with categories for the primary tumour, regional lymph nodes and distant metastases:

      TX: cannot evaluate the primary tumour T0: no evidence of tumour

      T1: tumour present, but not detectable clinically or with imaging T1a: tumour was incidentally found in less than 5% of prostate tissue resected (for other reasons)

      T1b: tumour was incidentally found in more than 5% of prostate tissue resected

      T1c: tumour was found in a needle biopsy performed due to an elevated serum prostate-specific antigen

      T2: the tumour can be felt (palpated) on examination, but has not spread outside the prostate

      T2a: the tumour is in half or less than half of one of the prostate gland’s two lobes

      T2b: the tumour is in more than half of one lobe, but not both

      T2c: the tumour is in both lobes

      T3: the tumour has spread through the prostatic capsule (if it is only part-way through, it is still T2)

      T3a: the tumour has spread through the capsule on one or both sides

      T3b: the tumour has invaded one or both seminal vesicles

      T4: the tumour has invaded other nearby structures.

      In this case, the tumour has a T1c stage.

    • This question is part of the following fields:

      • Pathology
      • Urology
      5.8
      Seconds
  • Question 43 - Severe abdominal pain radiating to the back, along with increased serum amylase levels,...

    Correct

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

      Your Answer: Pancreatitis

      Explanation:

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

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      9.4
      Seconds
  • Question 44 - The likely cause of a tender and swollen breast in a lactating mother...

    Correct

    • The likely cause of a tender and swollen breast in a lactating mother is:

      Your Answer: Acute mastitis

      Explanation:

      Acute mastitis results due to bacterial infection of the breast and results in signs of inflammation. It commonly occurs 2-3 weeks postpartum and common causative microorganisms are Staphylococcus aureus, Streptococcus species, and Escherichia coli. Complications like an abscess can be avoided by prompt treatment, which includes antibiotics and rest along with continued lactation.

    • This question is part of the following fields:

      • Pathology
      • Women's Health
      5
      Seconds
  • Question 45 - Which of the following structures is not easily palpable? ...

    Correct

    • Which of the following structures is not easily palpable?

      Your Answer: Styloid process of the temporal bone

      Explanation:

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

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      5.4
      Seconds
  • Question 46 - The oesophagus is an important part of the alimentary canal. It receives blood...

    Correct

    • The oesophagus is an important part of the alimentary canal. It receives blood from various arteries in the body. Which one of the following is an artery that will lead to some level of ischaemia to the oesophagus when ligated?

      Your Answer: Left inferior phrenic

      Explanation:

      The oesophagus receives its blood supply from the following arteries: the inferior thyroid branch of the thyrocervical trunk, the descending thoracic aorta, the left gastric branch of the coeliac artery and the from the left inferior phrenic artery of the abdominal aorta. Hence ligation of the left inferior phrenic will lead to ischemia to some portions of the oesophagus.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      49
      Seconds
  • Question 47 - A 34-year-old Asian male presents with cervical lymphadenopathy. The patient is suspected to...

    Correct

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

      Your Answer: Caseation necrosis

      Explanation:

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

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      60.5
      Seconds
  • Question 48 - A 65-year old patient with altered bowl movement experienced the worsening of...

    Correct

    • A 65-year old patient with altered bowl movement experienced the worsening of shortness of breath and exertional chest pains over the course of 8 weeks. Examination shows pallor and jugular venous distension. Furthermore, a test of the stool for occult blood is positive. Laboratory studies show:

      Haemoglobin 7.4 g/dl

      Mean corpuscular volume 70 fl Leukocyte count 5400/mm3

      Platelet count 580 000/mm3 Erythrocyte sedimentation 33 mm/h

      A blood smear shows hypochromic, microcytic RBCs with moderate poikilocytosis. Which of the following is the most likely diagnosis?

      Your Answer: Iron deficiency anaemia

      Explanation:

      Iron deficiency anaemia is the most common type of anaemia. It can occur due to deficiency of iron due to decreased intake or due to faulty absorption. An MCV less than 80 will indicated iron deficiency anaemia. On the smear the RBC will be microcytic hypochromic and will also show piokilocytosis. iron profiles tests are important to make a diagnosis. Clinically the patient will be pale and lethargic.

    • This question is part of the following fields:

      • General
      • Physiology
      27
      Seconds
  • Question 49 - If the blood flow is constant, oxygen extraction by tissues will show the...

    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.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      31
      Seconds
  • Question 50 - A 45-year old male, who was a chronic smoker presented to the clinic...

    Correct

    • A 45-year old male, who was a chronic smoker presented to the clinic with backache and dry, incessant cough. On examination, he was found to have raised blood pressure, purplish striae on his abdomen, truncal obesity and tenderness over the lower thoracic spine. These findings are suggestive of which condition?

      Your Answer: Small-cell anaplastic (oat cell) carcinoma

      Explanation:

      The symptoms suggest Cushing syndrome due to increased glucocorticoid levels. One cause of Cushing syndrome is ectopic production of adrenocorticotrophic hormone from oat cell carcinoma. As oat cell carcinoma is known to be highly metastatic, the tenderness in lower back could represent metastatic involvement.

    • This question is part of the following fields:

      • Endocrine
      • Pathology
      9.3
      Seconds
  • Question 51 - The primary motor cortex is located in the: ...

    Correct

    • The primary motor cortex is located in the:

      Your 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).

    • This question is part of the following fields:

      • Neurology
      • Physiology
      4.3
      Seconds
  • Question 52 - What are some of the derivatives of the second pharyngeal arch? ...

    Incorrect

    • What are some of the derivatives of the second pharyngeal arch?

      Your Answer: Stylopharyngeus muscle

      Correct Answer: Stylohyoid muscle

      Explanation:

      Also known as the hyoid arch, it forms the side and front of the neck. From its cartilage develops the styloid process, stylohyoid ligament and lesser cornu of the hyoid bone. The muscular derivatives include the muscles of facial expression, stapedius, stylohyoid and the posterior belly of the digastric. All these are innervated by cranial nerve VII but migrate into the area of the mandibular arch.

    • This question is part of the following fields:

      • Anatomy
      • Embryology
      10.5
      Seconds
  • Question 53 - What intrinsic muscle of the larynx is responsible for the tensing of the...

    Correct

    • What intrinsic muscle of the larynx is responsible for the tensing of the vocal cords?

      Your Answer: Cricothyroid muscle

      Explanation:

      The cricothyroid muscle is the only tensor muscle of the larynx aiding with phonation. It attaches to the anterolateral aspect of the cricoid and the inferior cornu and lower lamina of the thyroid cartilage. Its action tilts the thyroid forward to help tense the vocal cords.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      5.5
      Seconds
  • Question 54 - The left lateral pterygoid muscle is one of the muscles of mastication. When...

    Correct

    • The left lateral pterygoid muscle is one of the muscles of mastication. When acting alone, it will shift the mandible towards which direction?

      Your Answer: Laterally, to the right

      Explanation:

      The lateral pterygoid or external pterygoid is a muscle of mastication with two heads. It lies superiorly to the medial pterygoid. When acting alone, it will shift the mandible laterally and to the right.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      9.7
      Seconds
  • Question 55 - Which lymph nodes are likely to be enlarged in a patient who has...

    Incorrect

    • Which lymph nodes are likely to be enlarged in a patient who has malignant growth involving the anus?

      Your Answer: Periaortic

      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.

    • This question is part of the following fields:

      • Anatomy
      • Pelvis
      15.4
      Seconds
  • Question 56 - After a severe asthma attack, a 26-year-old woman is left in a markedly...

    Correct

    • After a severe asthma attack, a 26-year-old woman is left in a markedly hypoxic state. In which of the following organs are the arterial beds most likely to be vasoconstricted due to the hypoxia?

      Your Answer: Lungs

      Explanation:

      Hypoxic pulmonary vasoconstriction is a local response to hypoxia resulting primarily from constriction of small muscular pulmonary arteries in response to reduced alveolar oxygen tension. This unique response of pulmonary arterioles results in a local adjustment of perfusion to ventilation. This means that if a bronchiole is obstructed, the lack of oxygen causes contraction of the pulmonary vascular smooth muscle in the corresponding area, shunting blood away from the hypoxic region to better-ventilated regions. The purpose of hypoxic pulmonary vasoconstriction is to distribute blood flow regionally to increase the overall efficiency of gas exchange between air and blood.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      5.5
      Seconds
  • Question 57 - A 40-year old lady presented to the hospital with fever and mental confusion...

    Correct

    • A 40-year old lady presented to the hospital with fever and mental confusion for 1 week. On examination, she was found to have multiple petechiae all over her skin and mucosal surfaces. Blood investigations revealed low platelet count and raised urea and creatinine. A platelet transfusion was carried out, following which she succumbed to death. Autopsy revealed pink hyaline thrombi in myocardial arteries. What is the likely diagnosis?

      Your Answer: Thrombotic thrombocytopenic purpura

      Explanation:

      Hyaline thrombi are typically associated with thrombotic thrombocytopenic purpura (TTP), which is caused by non-immunological destruction of platelets. Platelet transfusion is contraindicated in TTP. Platelets and red blood cells also get damaged by loose strands of fibrin deposited in small vessels. Multiple organs start developing platelet-fibrin thrombi (bland thrombi with no vasculitis) typically at arteriocapillary junctions. This is known as ‘thrombotic microangiopathy’. Treatment consists of plasma exchange.

    • This question is part of the following fields:

      • Haematology
      • Pathology
      15.6
      Seconds
  • Question 58 - The blood-brain barrier is a membrane that separates the circulating blood from the...

    Correct

    • The blood-brain barrier is a membrane that separates the circulating blood from the brain extracellular fluid in the central nervous system (CNS). Which of the following statements regarding the blood– brain barrier is CORRECT?

      Your Answer: It breaks down in areas of brain that are infected

      Explanation:

      The blood–brain barrier is a membrane that controls the passage of substances from the blood into the central nervous system. It is a physical barrier between the local blood vessels and most parts of the central nervous system and stops many substances from travelling across it. During meningitis, the blood–brain barrier may be disrupted. This disruption may increase the penetration of various substances (including either toxins or antibiotics) into the brain. A few regions in the brain, including the circumventricular organs, do not have a blood–brain barrier.

    • This question is part of the following fields:

      • Fluids & Electrolytes
      • Physiology
      20.6
      Seconds
  • Question 59 - After being admitted to the hospital, a 60-year-old man is administered sodium nitroprusside....

    Correct

    • After being admitted to the hospital, a 60-year-old man is administered sodium nitroprusside. Which class of drugs does nitroprusside belong to?

      Your Answer: Vasodilators

      Explanation:

      Sodium nitroprusside is a potent peripheral vasodilator that affects both arterioles and venules. It is often administered intravenously to patients who are experiencing a hypertensive emergency. It reduces both total peripheral resistance as well as venous return, so decreasing both preload and afterload. For this reason it can be used in severe cardiogenic heart failure where this combination of effects can act to increase cardiac output. It is administered by intravenous infusion. Onset is typically immediate and effects last for up to ten minutes. The duration of treatment should not exceed 72 hours.

    • This question is part of the following fields:

      • Pathology
      • Pharmacology
      8.2
      Seconds
  • Question 60 - Diuretics that act on the ascending limb of the loop of Henle produce:...

    Correct

    • Diuretics that act on the ascending limb of the loop of Henle produce:

      Your Answer: Reduced active transport of sodium

      Explanation:

      The loop of Henlé leads from the proximal convoluted tubule to the distal convoluted tubule. Its primary function uses a counter current multiplier mechanism in the medulla to reabsorb water and ions from the urine. It can be divided into four parts:

      1. Descending limb of loop of Henlé – low permeability to ions and urea, while being highly permeable to water

      2. Thin ascending limb of loop of Henlé – not permeable to water, but it is permeable to ions

      3. Medullary thick ascending limb of loop of Henlé – sodium (Na+), potassium (K+) and chloride (Cl–) ions are reabsorbed by active transport. K+ is passively transported along its concentration gradient through a K+ channel in the basolateral aspect of the cells, back into the lumen of the ascending limb.

      4. The cortical thick ascending limb – the site of action where loop diuretics such as furosemide block the K+/Na+/2Cl− co-transporters = reduced active transport.

    • This question is part of the following fields:

      • Physiology
      • Renal
      11.4
      Seconds
  • Question 61 - A 60-year old gentleman visited his general practitioner complaining of high grade fever...

    Correct

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

      Your Answer: White blood cell casts

      Explanation:

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

    • This question is part of the following fields:

      • Pathology
      • Renal
      24.8
      Seconds
  • Question 62 - A 40-year old gentleman underwent a computed tomographic scan for the abdomen to...

    Correct

    • A 40-year old gentleman underwent a computed tomographic scan for the abdomen to rule out blunt abdominal trauma, after a vehicular accident. The scan revealed no abnormal finding except for a 1 cm-sized cortical mass in the left adrenal gland. The doctor-on-call decided to not intervene for this mass because it was likely to be a:

      Your Answer: Non-functioning adrenal adenoma

      Explanation:

      Adrenal adenomas are common, benign lesions which are asymptomatic and seen in 10% of population. Usually detected incidentally on Computed tomography (‘incidentaloma’), only around 1 in 10,000 are malignant (adenocarcinoma). Adrenal adenomas rarely need to be investigated, especially if they are homogenous and less than 3 cm in diameter. Follow-up imaging can be done after an interval of 3-6 months to assess any change in size. Some adenomas can secrete cortisol (leading to Cushing syndrome), or aldosterone (leads to Conn syndrome) or androgens (leading to hyperandrogenism).

      Haematomas and simple cysts are not usually seen in adrenal gland. Infection due to Histoplasma capsulatum is usually bilateral and leads to multiple granulomas. Adrenal metastasis will usually demonstrate a lung primary and the adrenal lesions will be often multiple and larger than 1 cm.

    • This question is part of the following fields:

      • Endocrine
      • Pathology
      12.8
      Seconds
  • Question 63 - A 45-year-old man complains of shortness of breath, cough and chest pain. Chest...

    Incorrect

    • A 45-year-old man complains of shortness of breath, cough and chest pain. Chest X ray revealed a perihilar mass with bronchiectasis in the left mid-lung. Which of the following is most probably associated with these findings?

      Your Answer: Mesothelioma

      Correct Answer: Bronchial carcinoid

      Explanation:

      Bronchial carcinoids are neuroendocrine tumours that arise from Kulchitsky’s cells of the bronchial epithelium. Kulchitsky’s cells belong to the diffuse endocrine system. Patients affected by this tumour may be asymptomatic or may present with symptoms of airway obstruction, like dyspnoea, wheezing, and cough. Other common findings are recurrent pneumonia, haemoptysis, chest pain and paraneoplastic syndromes. Chest radiographs are abnormal in the majority of cases. Peripheral carcinoids usually present as a solitary pulmonary nodule. For central lesions common findings include hilar or perihilar masses with or without atelectasis, bronchiectasis, or consolidation. Bronchial carcinoids most commonly arise in the large bronchi causing obstruction.

    • This question is part of the following fields:

      • Pathology
      • Respiratory
      54.3
      Seconds
  • Question 64 - After surgery, a patient developed a stitch granuloma . Which leukocyte in the...

    Correct

    • After surgery, a patient developed a stitch granuloma . Which leukocyte in the peripheral blood will become an activated macrophage in this granuloma?

      Your Answer: Monocyte

      Explanation:

      Monocytes are leukocytes that protect the body against infections and move to the site of infection within 8-12 hours to deal with it. They are produced in the bone marrow and shortly after being produced are released into the blood stream where they circulate until an infection is detected. When called upon they leave the circulation and transform into macrophages within the tissue fluid and thus gain the capability to phagocytose the offending substance. Monocyte count is part of a complete blood picture. Monocytosis is the state of excess monocytes in the peripheral blood and may be indicative of various disease states. Examples of processes that can increase a monocyte count include: • chronic inflammation • stress response • hyperadrenocorticism • immune-mediated disease • pyogranulomatous disease • necrosis • red cell regeneration.

    • This question is part of the following fields:

      • General
      • Physiology
      12.6
      Seconds
  • Question 65 - Which of the following is a true statement regarding the pupil? ...

    Incorrect

    • Which of the following is a true statement regarding the pupil?

      Your Answer: Atropine causes pupil constriction

      Correct Answer: Phentolamine causes pupil constriction

      Explanation:

      A balance between the sympathetic tone to the radial fibres of the iris and parasympathetic tone to the pupillary sphincter muscle determines the pupil size. Phentolamine (α-adrenergic receptor blocker) causes pupillary constriction. Dilatation of the pupil occurs with increased sympathetic activity, decreased parasympathetic activity during darkness or block of muscarinic receptors by atropine.

    • This question is part of the following fields:

      • Neurology
      • Physiology
      17.4
      Seconds
  • Question 66 - The cranial nerves of the brain provide motor and sensory innervation to the...

    Correct

    • The cranial nerves of the brain provide motor and sensory innervation to the structures of the head and neck. Which of the following cranial nerves provide only motor innervation?

      Your Answer: Abducens

      Explanation:

      The cranial nerves emerge directly from the brain and the brain stem. They provide sensory, motor or both motor and sensory innervation. Here is a summary of the cranial nerves and their function:

      Olfactory – Purely sensory

      Optic – Sensory

      Oculomotor – Mainly motor

      Trochlear – Motor

      Trigeminal – Both sensory and motor

      Abducens – Mainly motor

      Facial – Both sensory and motor

      Vestibulocochlear – Mostly sensory

      Glossopharyngeal – Both sensory and motor

      Vagus – Both sensory and motor

      Accessory – Mainly motor

      Hypoglossal – Mainly motor

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      59.9
      Seconds
  • Question 67 - A woman that presented with dyspnoea, chest pain and cough was found to...

    Correct

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

      Your Answer: Congestive heart failure

      Explanation:

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

    • This question is part of the following fields:

      • Pathology
      • Respiratory
      5.5
      Seconds
  • Question 68 - A 17-year-old female was given an antibiotic for a urinary tract infection. After...

    Correct

    • A 17-year-old female was given an antibiotic for a urinary tract infection. After taking the medication the patient developed Steven-Johnson syndrome. Which particular antibiotic usually causes Steven-Johnson syndrome?

      Your Answer: Sulphonamides

      Explanation:

      Stevens–Johnson syndrome (SJS) is a type of severe skin reaction. The most common cause is certain medications such as lamotrigine, carbamazepine, allopurinol, sulphonamide antibiotics, and nevirapine.

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      3.1
      Seconds
  • Question 69 - Renal function is an indication of the state of the kidney, measured by glomerular...

    Correct

    • Renal function is an indication of the state of the kidney, measured by glomerular filtration rate (GFR). In a healthy person, GFR would be greatly increased by: 

      Your Answer: Substantial increases in renal blood flow

      Explanation:

      An increase in the rate of renal blood flow (RBF) greatly increases the glomerular filtration rate (GFR). The more plasma available (from increased RBF), the more filtrate is formed. Glomerular filtration rate (GFR) is the volume of fluid filtered from the renal (kidney) glomerular capillaries into the Bowman’s capsule per unit time. Central to the physiologic maintenance of GFR is the differential basal tone of the afferent and efferent arterioles.

    • This question is part of the following fields:

      • Physiology
      • Renal
      8.7
      Seconds
  • Question 70 - A patient under went repair of a lingual artery aneurysm in the floor...

    Correct

    • A patient under went repair of a lingual artery aneurysm in the floor of the mouth. During surgical dissection from the inside of the mouth which muscle would you have to pass through to reach the main portion of the lingual artery?

      Your Answer: Hyoglossus

      Explanation:

      The lingual artery first runs obliquely upward and medialward to the greater horns of the hyoid bone. It then curves downward and forward, forming a loop which is crossed by the hypoglossal nerve, and passing beneath the digastric muscle and stylohyoid muscle it runs horizontally forward, beneath the hyoglossus, and finally, ascending almost perpendicularly to the tongue, turns forward on its lower surface as far as the tip, to become the deep lingual artery.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      7.2
      Seconds
  • Question 71 - The pterygoid plexus receives tributaries from which of the following veins? ...

    Correct

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

      Your Answer: Maxillary vein

      Explanation:

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

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      21.7
      Seconds
  • Question 72 - A 7-year-old boys undergoes a testicular biopsy after a tumour is found in...

    Correct

    • A 7-year-old boys undergoes a testicular biopsy after a tumour is found in his right testis. Elements similar to hair and teeth are found in it. What kind of tumour is this?

      Your Answer: Teratoma

      Explanation:

      A teratoma is a tumour containing tissue elements that are similar to normal derivatives of more than one germ layer. They usually contain skin, hair, teeth and bone tissue and are more common in children, behaving as a benign tumour. After puberty, they are regarded as malignant and can metastasise.

    • This question is part of the following fields:

      • Pathology
      • Urology
      8.5
      Seconds
  • Question 73 - Which cells are most commonly seen in a granulomatous lesion that suggests an...

    Incorrect

    • Which cells are most commonly seen in a granulomatous lesion that suggests an underlying chronic inflammation?

      Your Answer: Mast cells

      Correct Answer: Lymphocytes

      Explanation:

      Lymphocytes and monocytes are commonly and characteristically recognised in a case of chronic inflammation.

      Eosinophils and neutrophils are seen with acute inflammation.

      Mast cells release histamine in early inflammation.

      Basophils are seen with allergies.

      Plasma cells are seen with viral infection.

      Platelets are not characteristic of any type of inflammation.

    • This question is part of the following fields:

      • Inflammation & Immunology
      • Pathology
      14.2
      Seconds
  • Question 74 - C5a (a complement component) is a potent? ...

    Incorrect

    • C5a (a complement component) is a potent?

      Your Answer: Cytokine

      Correct 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.

    • This question is part of the following fields:

      • General
      • Physiology
      10.2
      Seconds
  • Question 75 - Which Statement is true of the brachial plexus? ...

    Correct

    • Which Statement is true of the brachial plexus?

      Your Answer: The posterior cord continues as the axillary nerve

      Explanation:

      The lateral cord continues as the musculocutaeous nerve.

      The medial cord continues as the ulnar nerve.

      The posterior cord continues as the radial nerve and the axillary nerve.

      The nerve to subclavius muscle is a branch of the C6 root.

      The suprascapular nerve is a branch from the upper trunk.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      17
      Seconds
  • Question 76 - A space defined by the teres major muscle, the teres minor muscle, long...

    Correct

    • A space defined by the teres major muscle, the teres minor muscle, long head of the triceps brachii muscle and surgical neck of the humerus contains the axillary nerve and the?

      Your Answer: Posterior circumflex humeral artery

      Explanation:

      This quadrangular space transmits the posterior circumflex humeral vessels and the axillary nerve.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      15.3
      Seconds
  • Question 77 - If a catheter is placed in the main pulmonary artery of a healthy...

    Correct

    • If a catheter is placed in the main pulmonary artery of a healthy 30-year-old woman, which of the following will be its mean pulmonary arterial pressure?

      Your Answer: 15 mmHg

      Explanation:

      The pulmonary artery pressure (PA pressure) is a measure of the blood pressure found in the main pulmonary artery. The hydrostatic pressure of the pulmonary circulation refers to the actual pressure inside pulmonary vessels relative to atmospheric pressure. Hydrostatic (blood pressure) in the pulmonary vascular bed is low compared with that of similar systemic vessels. The mean pulmonary arterial pressure is about 15 mmHg (ranging from about 13 to 19 mmHg) and is much lower than the average systemic arterial pressure of 90 mmHg.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      7.8
      Seconds
  • Question 78 - Which is the correct order of tendons passing from medial to lateral-posterior to...

    Incorrect

    • Which is the correct order of tendons passing from medial to lateral-posterior to the medial malleolus?

      Your Answer: Flexor digitorum longus, flexor hallucis longus, posterior tibial

      Correct Answer: Posterior tibial, flexor digitorum longus, flexor hallucis longus

      Explanation:

      The correct order of structures is the tendon of tibialis posterior, tendon of flexor digitorum longus, posterior tibial artery (and vein), tibial nerve and tendon of flexor hallucis longus.

    • This question is part of the following fields:

      • Anatomy
      • Lower Limb
      47.3
      Seconds
  • Question 79 - The Henderson–Hasselbalch equation describes the derivation of pH as a measure of acidity. According to this equation,...

    Correct

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

      Your Answer: Equal

      Explanation:

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

    • This question is part of the following fields:

      • Fluids & Electrolytes
      • Physiology
      4.4
      Seconds
  • Question 80 - A 25 year old primi gravida lady was scheduled for a regular antenatal...

    Incorrect

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

      Your Answer: Fundus of the uterus

      Correct Answer: Fundus of the bladder

      Explanation:

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

    • This question is part of the following fields:

      • Anatomy
      • Pelvis
      7.9
      Seconds
  • Question 81 - From which source does the lingual artery originate? ...

    Correct

    • From which source does the lingual artery originate?

      Your Answer: External carotid

      Explanation:

      The lingual artery arises from the external carotid between the superior thyroid artery and facial artery. It can be located easily on the lower surface of the tongue. The terminal branch of the lingual artery is the deep lingual artery. On its course the lingual artery gives off side branches: dorsal lingual branches that supply the dorsum of the tongue till the epiglottis; sublingual artery that supplies the sublingual gland.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      11.1
      Seconds
  • Question 82 - Calculate the cardiac output in an adult male with the following parameters:

    Heart...

    Correct

    • Calculate the cardiac output in an adult male with the following parameters:

      Heart rate 70 beats/min

      Arterial [O2] 0.24 ml O2/min

      Venous [O2] 0.16 ml O2/mi

      Whole body O2 consumption 500 ml/min

      Pulmonary diastolic pressure 15 mmHg

      Pulmonary systolic pressure 25 mmHg

      Wedge pressure 5 mmHg.

      Your Answer: 6.25 l/min

      Explanation:

      As per Fick’s principle, VO2 = (CO × CAO2) – (CO × CVO2) where VO2 = oxygen consumption, CO = cardiac output, CAO2 = oxygen concentration of arterial blood and CVO2 = oxygen concentration of venous blood. Thus, CO = VO2/CAO2– CVO2, CO = 500/0.24 – 0.16, CO = 500/0.8, CO = 6.25 l/min.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      11.6
      Seconds
  • Question 83 - A 38-year old lady presented to the hospital with abnormal passing of blood...

    Correct

    • A 38-year old lady presented to the hospital with abnormal passing of blood per vagina. On examination, she was found to have an endocervical polypoidal mass. On enquiry, she gave history of oral contraceptive usage for 3 years. What finding is expected on the histopathology report of biopsy of the mass?

      Your Answer: Microglandular hyperplasia

      Explanation:

      Endocervical polyps or microglandular hyperplasia are benign growths occurring in the endocervical canal, in about 2-5% women and occur secondary to use of oral contraceptives. They are usually < 1cm in size, friable and reddish-pink. Usually asymptomatic, they can cause bleeding or become infected, leading to leucorrhoea (purulent vaginal discharge). They are usually benign but need to be differentiated from adenocarcinomas by histology.

    • This question is part of the following fields:

      • Pathology
      • Women's Health
      8.5
      Seconds
  • Question 84 - A 22-year old man presented with a mass in his left scrotum which...

    Incorrect

    • A 22-year old man presented with a mass in his left scrotum which was more prominent when standing and felt like a 'bag of worms'. Examination revealed a non-tender mass along the spermatic cord. Also, the right testis was larger than the left testis. What is the likely diagnosis?

      Your Answer: Pyocoele

      Correct Answer: Varicocele

      Explanation:

      Varicocele refers to dilatation and increased tortuosity of the pampiniform plexus – which is a network of veins found in spermatic cord that drain the testicle. Defective valves or extrinsic compression can result in outflow obstruction and cause dilatation near the testis. Normal diameter of the small vessels ranges from 0.5 – 1.5mm. A varicocele is a dilatation more than 2mm.

      The plexus travels from the posterior aspect of testis into the inguinal canal with other structures forming the spermatic cord. They then form the testicular veins out of which the right testicular vein drains into the inferior vena cava and the left into the left renal vein.

      It affects 15-20% men, and 40% of infertile males. Usually diagnosed in 15-25 years of age, they are rarely seen after 40 years of age. Because of the vertical path taken by the left testicular vein to drain into left renal vein, 98% idiopathic varicoceles occur on the left side. It is bilateral in 70% cases. Right-sided varicoceles are rare.

      Symptoms include pain or heaviness in the testis, infertility, testicular atrophy, a palpable mass, which is non-tender and along the spermatic cord (resembling a ‘bag of worms’). The testis on the affected side might be smaller.

      Diagnosis can be made by ultrasound. Provocative measures such as Valsalva manoeuvre or making the patient stand up to increase the dilatation by increasing the intra-abdominal venous pressure.

    • This question is part of the following fields:

      • Pathology
      • Urology
      5.8
      Seconds
  • Question 85 - To reach the oral vestibule, the parotid duct must pierce this muscle: ...

    Incorrect

    • To reach the oral vestibule, the parotid duct must pierce this muscle:

      Your Answer: Cricothyroid muscle

      Correct Answer: Buccinator muscle

      Explanation:

      The parotid duct or Stensen duct is a duct and the route that saliva takes from the major salivary gland, the parotid gland into the mouth. The parotid duct is formed when several interlobular ducts—the largest ducts inside the parotid gland join. It emerges from the gland and runs forward along the lateral side of the masseter muscle. In this course, the duct is surrounded by the buccal fat pad. It takes a steep turn at the border of the masseter and passes through the buccinator muscle, opening into the vestibule of the mouth, between the cheek and the gums, at the parotid papilla, which lies across the second superior molar tooth.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      8.8
      Seconds
  • Question 86 - A patient with this type of tumour is advised to follow up regularly...

    Incorrect

    • A patient with this type of tumour is advised to follow up regularly for monitoring of tumour size as there is a strong correlation with malignant potential and tumour size. Which of the following is the most likely tumour in this patient?

      Your Answer: Breast adenocarcinoma

      Correct Answer: Renal adenocarcinoma

      Explanation:

      The distinction between a benign renal adenoma and renal adenocarcinoma is commonly made on the basis of size. Tumours less than 2 cm in size rarely become malignant as opposed to those greater than 3 cm.

    • This question is part of the following fields:

      • Neoplasia
      • Pathology
      22.4
      Seconds
  • Question 87 - Which of the following is NOT true regarding malignant hyperpyrexia ...

    Incorrect

    • Which of the following is NOT true regarding malignant hyperpyrexia

      Your Answer: It can be caused by suxamethonium

      Correct Answer: It can be caused by nitrous oxide

      Explanation:

      Malignant hyerpyrexia occurs in 1 in 150,000. All inhalational anaesthetic agents and suxamethonium, except nitrous oxide can cause malignant hyperpyrexia.

    • This question is part of the following fields:

      • Pathology
      • Pharmacology
      4.5
      Seconds
  • Question 88 - An enlarged lymph node which shows well-defined, prominent paracortical follicles with germinal centres...

    Incorrect

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

      Your Answer: A 58-year-old man with Bence Jones proteins in the urine

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

      Explanation:

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

    • This question is part of the following fields:

      • Haematology
      • Pathology
      13.9
      Seconds
  • Question 89 - A patient is diagnosed with Brucellosis. What is the mode of transmission of...

    Incorrect

    • A patient is diagnosed with Brucellosis. What is the mode of transmission of this disease?

      Your Answer: Cats

      Correct Answer: Unpasteurised milk

      Explanation:

      Brucellosis is a highly contagious zoonosis caused by ingestion of unpasteurized milk or undercooked meat from infected animals, or close contact with their secretions.

    • This question is part of the following fields:

      • Microbiology
      • Pathology
      5.6
      Seconds
  • Question 90 - During a case presentation, a 26 year old is said to have fractured...

    Incorrect

    • During a case presentation, a 26 year old is said to have fractured his pelvis and shattered his coccyx following a motorbike accident. It is mentioned that he is likely to have lacerated his middle sacral artery from this kind of injury. Where does the middle sacral artery branch from?

      Your Answer: Common iliac artery

      Correct Answer: Abdominal aorta

      Explanation:

      The middle sacral artery arises from behind the aorta a little above the point of its bifurcation to descend down in front of L4,5, the sacrum and coccyx.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      4.1
      Seconds
  • Question 91 - Which organ is responsible for the secretion of enzymes that aid in digestion...

    Incorrect

    • Which organ is responsible for the secretion of enzymes that aid in digestion of complex starches?

      Your Answer: Stomach

      Correct Answer: Pancreas

      Explanation:

      α-amylase is secreted by the pancreas, which is responsible for hydrolysis of starch, glycogen and other carbohydrates into simpler compounds.

    • This question is part of the following fields:

      • Gastroenterology
      • Physiology
      23.5
      Seconds
  • Question 92 - Which muscle in the neck divides the neck into two large triangles? ...

    Correct

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

      Your Answer: Sternocleidomastoid

      Explanation:

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

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      45.2
      Seconds
  • Question 93 - Which of the following associations is correctly matched with the body's defence mechanism...

    Correct

    • Which of the following associations is correctly matched with the body's defence mechanism in fighting infection?

      Your 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
      14.6
      Seconds
  • Question 94 - Calculate the cardiac stroke volume of a patient whose oxygen consumption (measured by...

    Incorrect

    • Calculate the cardiac stroke volume of a patient whose oxygen consumption (measured by analysis of mixed expired gas) is 300 ml/min, arterial O2 content is 20 ml/100 ml blood, pulmonary arterial O2 content is 15 ml/100 ml blood and heart rate is 60/min.

      Your Answer: 20 ml

      Correct Answer: 100 ml

      Explanation:

      By Fick’s principle, VO2 = Q × (CA (O2) − CV (O2)) where VO2 = O2 consumption, Q = cardiac output and CA(O2) and CV(O2) are arterial and mixed venous O2 content respectively. Thus, in the given problem, 300 ml O2/min = Q × (20−15) ml O2/100 ml. Thus, Q = 6000 ml blood/min. Then, we can calculate stroke volume by dividing the cardiac output with heart rate. Thus, stroke volume = 6000 ml/min divided by 60/min stroke volume = 100 ml.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      24.2
      Seconds
  • Question 95 - In which of the following conditions will the oxygen-haemoglobin dissociation curve shift to...

    Incorrect

    • In which of the following conditions will the oxygen-haemoglobin dissociation curve shift to the right?

      Your Answer: Decrease in p(CO2)

      Correct Answer: Exercise

      Explanation:

      The oxygen-haemoglobin dissociation curve plots saturated haemoglobin against the oxygen tension and is usually a sigmoid plot. Each molecule of haemoglobin can bind to four molecules of oxygen reversibly. Factors that can influence the binding include: pH, concentration of 2,3-diphosphoglycerate (2,3-DPG), temperature, type of haemoglobin molecules, and presence of toxins, especially carbon monoxide. Shape of the curve is due to interaction of bound oxygen molecules with the incoming molecules. The binding of first molecule is difficult, with easier binding of the second and third molecule and increase in difficulty with the fourth molecule – partly as a result of crowding and partly as a natural tendency of oxygen to dissociate.

      Left shift of curve indicates haemoglobin’s increased affinity for oxygen (seen at lungs). Right shift indicates decreased affinity and is seen with an increase in body temperature, hydrogen ions, 2,3-diphosphoglycerate (DPG), carbon dioxide concentration and exercise. Under normal resting conditions in a healthy individual, the normal position of the curve is at a pH of 7.4. A shift in the position of the curve with a change in pH is called the Bohr effect. Left shift occurs in acute alkalosis, decrease in p(CO2), decrease in temperature and decrease in 2,3-DPG. The fetal haemoglobin curve is to the left of the adult haemoglobin to allow for oxygen diffusion across the placenta. The curve for myoglobin is even further to the left. Carbon monoxide has a much higher affinity for haemoglobin than oxygen does. Thus, carbon monoxide poisoning leads to hypoxia.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      6.8
      Seconds
  • Question 96 - An 8 year old boy presents with a history of repeated bacterial/pyogenic infections....

    Incorrect

    • An 8 year old boy presents with a history of repeated bacterial/pyogenic infections. He had a normal recovery from chickenpox and measles and shows normal antibody response. A decrease in which of the cell types can best explain this history of repeated pyogenic infections?

      Your Answer: Eosinophils

      Correct Answer: Neutrophils

      Explanation:

      A decrease in the number of granulocytes, particularly neutrophils is known as agranulocytosis and it increases the susceptibility of an individual towards recurrent infections. Neutropenia can be either due to decreased production or increased elimination of neutrophils.

      Ineffective agranulopoiesis is seen in: 1. myeloid stem cell suppression, 2. disease conditions associated with granulopoiesis such as megaloblastic anaemia and myelodysplastic syndromes, 3. rare genetic diseases, 4. splenic sequestration and 5. increased peripheral utilization.

    • This question is part of the following fields:

      • Inflammation & Immunology
      • Pathology
      13.9
      Seconds
  • Question 97 - A 46 -year old patient diagnosed with chronic rhinosinusitis, was to undergo surgery...

    Incorrect

    • A 46 -year old patient diagnosed with chronic rhinosinusitis, was to undergo surgery to improve drainage from his frontal sinus to the nose. Which is a route that one would take to enter into the frontal sinus through the nasal cavity?

      Your Answer: Sphenoethmoidal recess

      Correct Answer: Middle meatus

      Explanation:

      The middle meatus is a nasal passageway located inferior to the middle concha and superior to the inferior concha. On the superior aspect of this meatus is a bulge produced by the middle ethmoidal cells known as the bulla ethmoidalis. Below this bulge is a curved fissure, the hiatus semilunaris, which is also bordered inferiorly by the edge of the uncinate process of the ethmoid. It is through this curved fissure, hiatus semilunaris, that the middle meatus communicates with the frontal sinus. It first forms a communication with a curved passage way known as the infundibulum. The infundibulum anteriorly communicates with the anterior ethmoidal cells and continues upward as the frontonasal duct into the frontal sinus.

    • This question is part of the following fields:

      • Anatomy
      • Head & Neck
      27.7
      Seconds
  • Question 98 - Which of the following muscle divide the posterior triangle of the neck into...

    Incorrect

    • Which of the following muscle divide the posterior triangle of the neck into the occipital and the subclavian triangle?

      Your Answer: Scalenus anterior muscle

      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
      12.6
      Seconds
  • Question 99 - A patient who following 20 years of working in the asbestos industry develops...

    Incorrect

    • A patient who following 20 years of working in the asbestos industry develops malignant mesothelioma and is scheduled for pleuropneumonectomy to remove the entire pleura and lung on the affected side. Which layer would provide a natural cleavage plane for surgical separation of the costal pleura from the thoracic wall?

      Your Answer:

      Correct Answer: Endothoracic fascia

      Explanation:

      The endothoracic fascia is connective tissue that is between the costal parietal pleura and the inner aspect of the chest wall. Removing this layer of connective tissue would make it easy to separate the costal pleura from the thoracic wall.

      Deep fascia: is not found around the lungs. It is a layer of connective tissue that invests a muscle or a group of muscles.

      Parietal pleura: part of the pleura that lines the inner surface of the chest/thoracic cavity.

      Visceral pleura: is the serous membrane that lines the surface of the lungs.

      Transversus thoracis muscle fascia is associated only with the muscle transversus thoracis.

      Peritracheal fascia: a layer of connective tissue that invests the trachea. It is not associated with the thoracic wall or the costal pleura.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
      0
      Seconds
  • Question 100 - What will the destruction of endoplasmic reticulum stop? ...

    Incorrect

    • What will the destruction of endoplasmic reticulum stop?

      Your Answer:

      Correct Answer: Synthesis of proteins

      Explanation:

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

    • This question is part of the following fields:

      • General
      • Physiology
      0
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Microbiology (5/5) 100%
Pathology (23/32) 72%
Abdomen (10/12) 83%
Anatomy (29/39) 74%
Head & Neck (12/12) 100%
Neurology (2/3) 67%
Upper Limb (4/4) 100%
Lower Limb (2/6) 33%
Thorax (1/2) 50%
Gastroenterology (2/3) 67%
Physiology (21/27) 78%
Cardiovascular (5/5) 100%
Renal (5/5) 100%
Fluids & Electrolytes (3/4) 75%
Inflammation & Immunology; Haematology (0/1) 0%
Respiratory (4/7) 57%
Neoplasia (1/3) 33%
Inflammation & Immunology (1/4) 25%
Urology (2/3) 67%
Endocrinology (1/1) 100%
Orthopaedics (1/1) 100%
Haematology (3/3) 100%
General (4/6) 67%
Women's Health (1/1) 100%
Endocrine (2/2) 100%
Embryology (0/1) 0%
Pelvis (0/2) 0%
Pharmacology (2/2) 100%
Passmed