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Question 1
Correct
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Clostridium tetani causes which of the following infectious diseases:
Your Answer: Tetanus
Explanation:Clostridium tetani causes tetanus.
Scarlet fever is caused by Streptococcus pyogenes.
Toxic shock syndrome is caused by Staphylococcus aureus or Streptococcus pyogenes.
Gas gangrene is primarily caused by Clostridium perfringens.
Pseudomembranous colitis is commonly caused by Clostridium difficile. -
This question is part of the following fields:
- Microbiology
- Pathogens
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Question 2
Incorrect
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Which of these statements about the monospot test is true?
Your Answer:
Correct Answer: It can be positive in rubella
Explanation:Infectious mononucleosis can be diagnosed using specific EBV antibodies and a variety of unrelated non-EBV heterophile antibodies.
Heterophile antibodies:
About 70-90% of patients with EBV infectious mononucleosis produce antibodies against an antigen produced in one species that react against antigens from other species called heterophile antibodies. False positives can be seen with rubella, hepatitis, SLE, malaria, toxoplasmosis, lymphoma and leukaemia.These antibodies can be detected by two main screening tests:
The monospot test uses horse red blood cells. It agglutinates in the presence of heterophile antibodies.
Paul-Bunnell test uses sheep red blood cells. The blood agglutinates in the presence of heterophile antibodies.EBV-specific antibodies:
Patients can remain heterophile-negative after six weeks and are then considered to be heterophile-negative and should be tested for EBV-specific antibodies. EBV-specific antibodies test are helpful if a false positive heterophile antibody test is suspected.
The indirect Coombs test is used to detect in-vitro antibody-antigen reactions. It is typically used in antenatal antibody screening and in preparation for blood transfusion.
Heterophile antibody tests are generally not positive in the incubation period of infectious mononucleosis (4-6 weeks) before the onset of symptoms. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 3
Incorrect
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A 22-year-old student presents with severe headache accompanied with nausea and vomiting. Upon observation and examination, it was noted that he is febrile and Kernig's sign is positive. A diagnosis of meningitis was suspected and a lumbar puncture was to be performed.
Which of the following statements regarding meningitis is true?Your Answer:
Correct Answer: The dura mater is the outermost layer
Explanation:Meningitis is defined as the inflammation of the meninges due to an infection caused by a bacteria or a virus. Symptoms usually include stiffness of the neck, headache, and fever.
There are 3 meningeal layers that surround the spinal cord and they are the dura mater, arachnoid matter, and pia mater.The dura mater is the outermost and thickest layer out of all the 3 layers.
The arachnoid atter is the middle layer, and is very thin.
The third and deepest meningeal layer is the pia mater that is bound tightly to the surface of the spinal cord. -
This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 4
Incorrect
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A patient is referred for lung function tests on account of a history of breathlessness and cough.
Which statement about lung volumes is correct?
Your Answer:
Correct Answer: The tidal volume is the volume of air drawn in and out of the lungs during normal breathing
Explanation:The tidal volume(TV) is the amount of air that moves in and out of the lungs with each respiratory cycle. In a healthy male, the usual volume is 0.5 L (,7 ml/kg body mass).
The vital capacity(VC) is the maximum amount of air that can be exhaled following maximal inspiration. The usual volume in a healthy male is 4.5 L.
The residual volume(RV) is the amount of air remaining in the lungs after maximum expiration. The usual volume in a healthy male is 1.0 L.
The inspiratory reserve volume(IRV) is the maximum amount of air that can be breathed in forcibly after normal inspiration. The usual volume in a healthy male is 3.0 L.
The expiratory reserve volume(ERV) is the volume of air that can be breathed out forcibly after normal expiration. The usual volume in a healthy male is 1.0 L.
Total lung capacity(TLC) is the volume of air the lungs can accommodate. TLC = RV+VC. The usual volume in a healthy male is 5.5 L.
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This question is part of the following fields:
- Physiology
- Respiratory Physiology
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Question 5
Incorrect
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During her pregnancy, a 28-year-old lady was given an antibiotic. The neonate was prematurely born with cyanosis and ashen grey coloured skin as a result of this. Other symptoms were hypotonia, low blood pressure, and poor feeding.
From the following antibiotics, which one is most likely to cause this side effect?Your Answer:
Correct Answer: Chloramphenicol
Explanation:Grey baby syndrome is a rare but causes significant adverse effect caused by the build-up of chloramphenicol in neonates (particularly preterm babies).
The following are the main characteristics of ‘grey baby syndrome’:
Skin that is ashy grey in colour.
Feeding problems
Vomiting
Cyanosis
Hypotension
Hypothermia
Hypotonia
Collapse of the cardiovascular system
Distension of the abdomen
trouble breathing -
This question is part of the following fields:
- Infections
- Pharmacology
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Question 6
Incorrect
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You examine a 43-year-old woman who was referred to you by a friend. She suffers from a variety of medical conditions and takes a variety of medications, including amitriptyline.
Which of the following is NOT a contraindication to amitriptyline treatment?Your Answer:
Correct Answer: Breastfeeding
Explanation:Amitriptyline is a tricyclic antidepressant (TCA) that is most commonly used to treat depression, but it can also be used to treat anxiety disorders, chronic pain, and attention deficit hyperactivity disorder (ADHD). It inhibits reuptake, raising serotonin and noradrenaline levels while also inhibiting acetylcholine action.
TCAs have a number of drawbacks, including:
Acute Porphyria
Arrhythmias
During bipolar disorder’s manic phase
Heart block
After a myocardial infarction, there is an immediate recovery period.TCA levels in breast milk are too low to be harmful, and use can be continued while breastfeeding.
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This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
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Question 7
Incorrect
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The following statements are not true of the extensor carpi radialis brevis muscle, except?
Your Answer:
Correct Answer: It receives its blood supply from the radial artery
Explanation:Extensor carpi radialis brevis is a fusiform muscle found in the lateral part of the posterior forearm. Together with anconaeus, brachioradialis, extensor carpi radialis longus, extensor digitorum, extensor digiti minimi and extensor carpi ulnaris, it belongs to the superficial forearm extensor group. Extensor carpi radialis brevis originates from the lateral epicondyle of humerus via the common extensor tendon. This is a common origin that it shares with the extensor digitorum, extensor digiti minimi and extensor carpi ulnaris muscles. Some fibres also originate from the lateral intermuscular septum, a thick aponeurosis that covers the muscle itself, and from the radial collateral ligament.
The muscle courses inferiorly, giving off a long tendon in the middle of the forearm which descends towards the dorsal hand. The tendon passes through a groove on the posterior surface of radius, deep to the extensor retinaculum. After traversing the extensor retinaculum space, the tendon inserts into the posterior aspect of the base of the third metacarpal bone.
Extensor carpi radialis brevis is innervated directly by the radial nerve (C5- C8), or sometimes from its deep branch/posterior interosseous nerve. The radial nerve stems from the posterior cord of the brachial plexus.
The muscle is vascularized by the radial recurrent artery, radial artery and deep brachial artery (via its radial collateral branch).
Extensor carpi radialis brevis works together with extensor carpi ulnaris and extensor carpi radialis longus to extend the hand at the wrist joint. This action is vital in a sequence of muscle contractions needed for clenching a fist or making a grip. When performing these functions, wrist extension blocks the flexor muscles from on acting upon the hand. Instead, flexors act only on the digits, thereby flexing them and producing an effective hand grip, such as that seen in a tennis backhand. When the extensor carpi radialis brevis muscle contracts together with extensor carpi radialis longus and flexor carpi radialis, it contributes to producing hand abduction (radial deviation).
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 8
Incorrect
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A novel anti-tuberculosis medicine was compared to standard treatment and shown to cut the risk of death from 30 to 10 per 1000 people. How many patients would need to be treated (number need to treat (NNT)) in order to prevent 10 additional tuberculosis deaths:
Your Answer:
Correct Answer: 500
Explanation:The risk of mortality in the control group (usual therapy) minus the risk of death in the treatment group equals the absolute risk reduction (ARR) of treatment.
30/1000 minus 10/1000 = 20/1000 = 0.02NNT = 1/ARR = 1/0.02 = 50
As a result, 50 people would need to be treated in order to prevent one additional fatality, and 500 people would need to be treated in order to avoid 10 additional deaths. -
This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 9
Incorrect
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What is the mechanism of action of penicillin antibiotics:
Your Answer:
Correct Answer: Inhibition of bacterial cell wall synthesis
Explanation:Penicillins and the other ß-lactam antibiotics are bactericidal. They produce their antimicrobial action by preventing cross-linkage between the linear peptidoglycan polymer chains that make up the bacterial cell wall. They, therefore, inhibit cell wall synthesis.
The integrity of the ß-lactam ring is essential for antimicrobial activity. Many bacteria (including most Staphylococci) are resistant to benzylpenicillin and phenoxymethylpenicillin because they produce enzymes (penicillinases, ß-lactamases) that open the ß-lactam ring. -
This question is part of the following fields:
- Infections
- Pharmacology
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Question 10
Incorrect
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Which of the following is typically a cause of a normal anion gap metabolic acidosis:
Your Answer:
Correct Answer: Diarrhoea
Explanation:FUSEDCARS can be used to remember some of the causes of a normal anion gap acidosis:
Fistula (pancreaticoduodenal)
Ureteroenteric conduit
Saline administration
Endocrine (hyperparathyroidism)
Diarrhoea
Carbonic anhydrase inhibitors (e.g. acetazolamide)
Ammonium chloride
Renal tubular acidosis
Spironolactone -
This question is part of the following fields:
- Physiology
- Renal
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Question 11
Incorrect
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When there is the presence of distended and engorged veins in the umbilical area, which of the following portosystemic anastomoses has most likely occurred?
Your Answer:
Correct Answer: Para-umbilical veins and inferior epigastric vein
Explanation:Caput medusae is a condition that consists of collateral veins radiating from the umbilicus and results from recanalization of the umbilical vein.
Under normal conditions, the portal venous blood traverses the liver and drains into the inferior vena cava of the systemic venous circulation by way of the hepatic veins. This is the direct route. However, other, smaller communications exist between the portal and systemic systems, and they become important when the direct route becomes blocked. These communications are as follows:
At the lower third of the oesophagus, the oesophageal branches of the left gastric vein (portal tributary) anastomose with the oesophageal veins draining the middle third of the oesophagus into the azygos veins (systemic tributary).
Halfway down the anal canal, the superior rectal veins (portal tributary) draining the upper half of the anal canal anastomosis with the middle and inferior rectal veins (systemic tributaries), which are tributaries of the internal iliac and internal pudendal veins, respectively.
The paraumbilical veins connect the left branch of the portal vein with the superficial veins of the anterior abdominal wall (systemic tributaries). The paraumbilical veins travel in the falciform ligament and accompany the ligamentum teres.
The veins of the ascending colon, descending colon, duodenum, pancreas, and liver (portal tributary) anastomose with the renal, lumbar, and phrenic veins (systemic tributaries).
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This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
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Question 12
Incorrect
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Which of the following statements is correct about the extensor digitorum muscle?
Your Answer:
Correct Answer: It extends the medial four digits at the metacarpophalangeal joints
Explanation:Extensor digitorum is a long muscle located in the posterior compartment of the forearm. Together with the extensor carpi ulnaris and extensor digiti minimi, extensor carpi radialis longus and brevis as well as the brachioradialis, it belongs to the group of superficial extensors of the forearm. These muscles can be easily palpated in the lateral aspect of the posterior forearm, especially during the extension of hand when they are contracted.
Extensor digitorum runs from the lateral epicondyle of humerus to the medial four phalanges of the hand. In this way, it generates the pull for the extension of the four medial fingers in their metacarpophalangeal and both interphalangeal joints. Extensor digitorum also participates in the extension of the wrist.
Extensor digitorum is innervated by posterior interosseous nerve which is a continuation of a deep branch of radial nerve (root value C7 and C8).
Extensor digitorum is vascularized by the branches of three different arteries: (1) posterior interosseous artery, (2) radial recurrent artery, and (3) anterior interosseous artery. Anterior and posterior interosseous arteries are the branches of the common interosseous artery that arises from the ulnar artery. The radial recurrent artery is a branch of the radial artery.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 13
Incorrect
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Question 14
Incorrect
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The cutaneous circulation is responsible for the skin's blood supply. Because the skin is not a highly metabolically active tissue with low energy requirements, its blood supply differs from that of other tissues. Instead of capillaries, some of the circulating blood volume in the skin passes through arteriovenous anastomoses (AVAs).
Which of the following statements regarding arteriovenous anastomoses is correct?
Your Answer:
Correct Answer: AVAs are innervated by sympathetic fibres originating from the hypothalamus
Explanation:Short vessels called arteriovenous anastomoses (AVAs) link tiny arteries and veins. They have a large lumen diameter. The strong and muscular walls allow AVAs to completely clog the vascular lumen, preventing blood flow from artery to vein (acting like a sphincter). When the AVAs open, they create a low-resistance connection between arteries and veins, allowing blood to flow into the limbs’ superficial venous plexuses. There is no diffusion of solutes or fluid into the interstitium due to their strong muscle walls.
AVAs are densely innervated by adrenergic fibres from the hypothalamic temperature-regulation centre. High sympathetic output occurs at normal core temperatures, inducing vasoconstriction of the AVAs and blood flow through the capillary networks and deep plexuses. When the temperature rises, sympathetic output decreases, producing AVA vasodilation and blood shunting from the artery to the superficial venous plexus. Heat is lost to the environment as hot blood rushes near to the skin’s surface.
AVAs are a specialized anatomical adaptation that can only be found in large quantities in the fingers, palms, soles, lips, and pinna of the ear. -
This question is part of the following fields:
- Cardiovascular Physiology
- Physiology
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Question 15
Incorrect
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A 60-year-old female has a past medical history of diverticular disease. She now presents in the clinic with crampy abdominal pain. The nurse at the triage suggests prescribing hyoscine butyl bromide to help relieve the abdominal pain. However, after administering this treatment, the patient develops a side-effect to the medication.
What side-effect of using hyoscine butyl bromide is she MOST likely to develop out of the following?Your Answer:
Correct Answer: Dry mouth
Explanation:Hyoscine butylbromide is an antispasmodic drug that blocks muscarinic receptors and reduces intestinal motility. It is used for gastrointestinal and genitourinary smooth muscle spasms and symptomatic relief of IBS.
It has the following side-effects:
1. Constipation
2. Dizziness
3. Drowsiness
4. Dry mouth
5. Dyspepsia
6. Flushing
7. Headache
8. Nausea and vomiting
9. Palpitations
10. Skin reactions
11. Tachycardia
12. Urinary disorders
13. Disorders of vision -
This question is part of the following fields:
- Gastrointestinal Pharmacology
- Pharmacology
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Question 16
Incorrect
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Blood flows from the left atrium into the left ventricle via:
Your Answer:
Correct Answer: The mitral valve
Explanation:Blood flows from the right atrium into the right ventricle via the tricuspid atrioventricular valve and from the left atrium into the left ventricle via the mitral atrioventricular valve. Blood is ejected from the right ventricle through the pulmonary semilunar valve into the pulmonary artery and from the left ventricle via the aortic semilunar valve into the aorta.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 17
Incorrect
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Which of the following does NOT typically cause a neutrophil leucocytosis:
Your Answer:
Correct Answer: Glandular fever
Explanation:Causes of neutrophil leucocytosis:
Bacterial infection
Inflammation and tissue necrosis (e.g. cardiac infarct, trauma, vasculitis, myositis)
Metabolic disorders (e.g. uraemia, acidosis, eclampsia, gout)
Pregnancy
Acute haemorrhage or haemolysis
Neoplasms of all types
Drugs (e.g. corticosteroid therapy, lithium, tetracyclines)
Asplenia
Myeloproliferative disorders (e.g. CML, essential thrombocythaemia, polycythaemia vera, myelofibrosis)
Rare inherited disorders -
This question is part of the following fields:
- Immune Responses
- Pathology
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Question 18
Incorrect
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Which of the following statements about propofol is TRUE:
Your Answer:
Correct Answer: Propofol has some antiemetic action.
Explanation:Propofol has some antiemetic properties. It’s for this reason that it’s used to treat postoperative nausea and vomiting. Propofol is mostly processed in the liver, with the kidneys excreting just around 1% of it unaltered. Propofol, unlike thiopental, does not produce tissue necrosis when it is extravasated. Propofol lowers intracranial pressure via lowering brain metabolic rate and cerebral blood flow. Propofol is thought to be safe for people with bronchial asthma and chronic obstructive pulmonary disease.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 19
Incorrect
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You examine a 72-year-old man who has recently begun bumetanide treatment for worsening heart failure.
Which of these statements about bumetanide is correct?Your Answer:
Correct Answer: It has better intestinal absorption than furosemide
Explanation:Bumetanide is a loop diuretic that is used to treat congestive heart failure. It is frequently used in patients who have failed to respond to high doses of furosemide.
It has a potency of about 40 times that of furosemide, with a 1 mg dose being roughly equivalent to a 40 mg dose of furosemide.
Seizures are not known to be triggered by bumetanide. In fact, it lowers the concentration of neuronal chloride, making GABA’s action more depolarizing, and it’s currently being tested as an antiepileptic in the neonatal period.It takes effect after 1 hour of oral administration, and diuresis takes 6 hours to complete.
Bumetanide absorbs much better in the intestine than furosemide. Because it has a higher bioavailability than furosemide, it is commonly used in patients with gut oedema.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 20
Incorrect
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Which of the following muscles is most responsible for thigh extension at the hip joint?
Your Answer:
Correct Answer: Hamstrings and gluteus maximus
Explanation:For hip extension, the gluteus maximus and hamstring muscles work together. To compensate for gluteus maximus weakness, the hamstring frequently acts as the primary hip extensor.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 21
Incorrect
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A 58-year-old man with a traumatic brain injury is brought into the ER. A medical student asks you about the processes that occur in the brain following a traumatic injury.
One of these best describes the central nervous systems response to injury.Your Answer:
Correct Answer: Degeneration of the axon occurs proximally before it occurs distally
Explanation:Following neuronal injury, as seen in traumatic brain injury, the axon undergoes anterograde degeneration. Degradation starts from the cell body (proximally) and progresses distally. The axon becomes fragmented and degenerates.
The brain shows no reactive changes to injury is incorrect. Following major injury such as stroke, the brain undergoes a process of liquefactive degeneration, which leaves cystic spaces within the brain.
Axonal regeneration does not occur to any significant extent within the central nervous system unlike what is seen in the peripheral nervous system.
Astrocytes undergo reactive gliosis, leaving behind a firm translucent tissue around sites of damage.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 22
Incorrect
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Insulin binds to the insulin receptor (IR) on cell surfaces to exert its action. The IR is a very specific transmembrane receptor belonging to the tyrosine kinase receptor class.
One of these also activates the IR:
Your Answer:
Correct Answer: IGF-I
Explanation:Insulin receptor (IR), in addition to being activated by insulin, is also activated by IGF-I and IGF-II.
The IR is a dimer with two identical subunits spanning the cell membrane and are connected by a single disulphide bond. The two sub-units include: The alpha chain situated on the exterior of the cell membrane and the beta chain spanning the cell membrane in a single segment.
When insulin is detected, the alpha chains move together folding around the insulin making the beta chains move together, converting them into an active tyrosine kinase. This initiates a phosphorylation cascade increasing the expression of GLUT4 and allowing uptake of glucose by cells.
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 23
Incorrect
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A 55-year-old female is urgently rushed into the Emergency Department as she complains of chest pain that is worse on breathing, shortness of breath, palpitations, and haemoptysis.
She undergoes a CT pulmonary angiogram, which reveals a large pulmonary embolus. She is immediately started on heparin and shifted to the acute medical ward.
Which of the following statements is true regarding heparin?Your Answer:
Correct Answer: It activates antithrombin III
Explanation:Heparin is a polymer of glycosaminoglycan. It occurs naturally and is found in mast cells. Clinically, it is used in two forms:
1. Unfractionated: widely varying polymer chain lengths
2. Low molecular weight: Smaller polymers onlyHeparin works by binding to and activating the enzyme inhibitor antithrombin III. Antithrombin III inactivates thrombin (factor IIa) by forming a 1:1 complex with thrombin. The heparin-antithrombin III complex also inhibits factor Xa and some other proteases involved with clotting. The heparin-ATIII complex can also inactivate IX, XI, XII, and plasmin.
Heparin is not thrombolytic or fibrinolytic. It prevents the progression of existing clots by inhibiting further clotting. The lysis of existing clots relies on endogenous thrombolytics.
Heparin is used for:
1. Prevention and treatment of venous thromboembolism
2. Treatment of disseminated intravascular coagulation
3. Treatment of fat embolism
4. Priming of haemodialysis and cardiopulmonary bypass machinesThere is no evidence that heparin is superior to low-molecular-weight heparins in preventing mortality from thrombosis.
Vitamin K is used to reverse the effects of warfarin but not heparin. For heparin, protamine sulphate is used to counteract its effects.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 24
Incorrect
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Which of the following conditions manifests hyperkalaemia as one of its symptoms?
Your Answer:
Correct Answer: Congenital adrenal hyperplasia
Explanation:Plasma potassium greater than 5.5 mmol/L is hyperkalaemia or elevated plasma potassium level. Among the causes of hyperkalaemia include congenital adrenal hyperplasia.
Congenital adrenal hyperplasia is a general term referring to autosomal recessive disorders involving a deficiency of an enzyme needed in cortisol and/or aldosterone synthesis. The level of cortisol and/or aldosterone deficiency affects the clinical manifestations of congenital adrenal hyperplasia. When it involves hypoaldosteronism, it can result in hyponatremia and hyperkalaemia. While hypercortisolism can cause hypoglycaemia.
The other causes of hyperkalaemia may include renal failure, excess potassium supplementation, Addison’s disease (adrenal insufficiency), renal tubular acidosis (type 4), rhabdomyolysis, burns, trauma, Tumour lysis syndrome, acidosis, and medications such as ACE inhibitors, angiotensin receptor blockers, NSAIDs, beta-blockers, digoxin, and suxamethonium.
Bartter’s syndrome is characterized by hypokalaemic alkalosis with normal to low blood pressure.
Type 1 and 2 renal tubular acidosis both cause hypokalaemia.
Gitelman’s syndrome is a defect of the distal convoluted tubule of the kidney. It causes metabolic alkalosis with hypokalaemia and hypomagnesemia.
And excessive liquorice ingestion causes hypermineralocorticoidism and hypokalaemia as well. Thus, among the choices, only congenital adrenal hyperplasia can cause hyperkalaemia
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This question is part of the following fields:
- Physiology
- Renal Physiology
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Question 25
Incorrect
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A 32-year-old asthmatic patient on theophylline as part of her asthma management presents to the Emergency Department with an unrelated medical condition.
Which of these drugs should be avoided?Your Answer:
Correct Answer: Clarithromycin
Explanation:Macrolide antibiotics (e.g. clarithromycin and erythromycin) are cytochrome P450 enzyme inhibitors. They increase blood levels of theophylline leading to hypokalaemia, and potentially increasing the risk of Torsades de pointes when they are prescribed together.
Co-prescription with theophylline should be avoided.
Factors that enhance theophylline clearance include cigarette smoking, carbamazepine, phenobarbital, phenytoin, primidone, and rifampin.
Medications that inhibit clearance include ethanol, ciprofloxacin, erythromycin, verapamil, propranolol, ticlopidine, tacrine, allopurinol, and cimetidine. -
This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
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Question 26
Incorrect
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One of these statements about significance tests is true.
Your Answer:
Correct Answer: A p value of less than 1 in 20 is considered ‘statistically significant’
Explanation:The p value is statistically significant when it is less than 0.05 (5% or 1 in 20).
Statistical significance is not the same as clinical significance.
The null hypothesis states that there is no difference between the groups.
The power of a study is the probability of correctly rejecting the null hypothesis when it is false.
A type I error occurs when the null hypothesis has been rejected when it is true. A type II error occurs when the null hypothesis has been accepted when it is actually false.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 27
Incorrect
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How does abciximab mediate its antiplatelet effect:
Your Answer:
Correct Answer: It is a GPIIb/IIIa inhibitor.
Explanation:Abciximab, eptifibatide and tirofiban are GPIIb/IIIa inhibitors, inhibiting platelet aggregation by preventing the binding of fibrinogen, von Willebrand factor and other adhesive molecules.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 28
Incorrect
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Which of the following is NOT a typical effect of cortisol:
Your Answer:
Correct Answer: Decreased protein catabolism
Explanation:Cortisol is a steroid hormone produced in the zona fasciculata of the adrenal cortex. It is released in response to stress and low blood glucose concentrations.
Cortisol acts to: raise plasma glucose by stimulating glycolysis and gluconeogenesis in the liver and inhibiting peripheral glucose uptake into storage tissues, increase protein breakdown in skeletal muscle, skin and bone to release amino acids, increase lipolysis from adipose tissues to release fatty acidsand at higher levels and mimic the actions of aldosterone on the kidney to retain Na+ and water and lose K+ ionssuppress the action of immune cells -
This question is part of the following fields:
- Endocrine
- Physiology
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Question 29
Incorrect
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Regarding co-amoxiclav, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: Clavulanic acid acts to inhibit cross-linking of bacterial peptidoglycan polymers.
Explanation:Co-amoxiclav consists of amoxicillin with the beta-lactamase inhibitor clavulanic acid. Clavulanic acid itself has no significant antibacterial activity but, by inactivating beta-lactamases, it makes the combination active against beta-lactamase-producing bacteria that are resistant to amoxicillin.The most common adverse effects of co-amoxiclav include nausea, vomiting, skin rash and diarrhoea. Pseudomembranous colitis should be considered if a person develops severe diarrhoea during or after treatment with co-amoxiclav. Cholestatic jaundice can occur either during or shortly after the use of co-amoxiclav. An epidemiological study has shown that the risk of acute liver toxicity was about 6 times greater with co-amoxiclav than with amoxicillin. Cholestatic jaundice is more common in patients above the age of 65 years and in men; these reactions have only rarely been reported in children. Jaundice is usually self-limiting and very rarely fatal.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 30
Incorrect
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Which of the following clinical features is most suggestive of a lesion of the occipital lobe:
Your Answer:
Correct Answer: Homonymous hemianopia
Explanation:Homonymous hemianopia is a visual field defect involving either the two right or the two left halves of the visual fields of both eyes. It is caused by lesions of the retrochiasmal visual pathways, ie, lesions of the optic tract, the lateral geniculate nucleus, the optic radiations, and the cerebral visual (occipital) cortex
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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SESSION STATS - PERFORMANCE PER SPECIALTY
