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Question 1
Incorrect
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Regarding cross-sectional studies, which of the following statements is CORRECT:
Your Answer: They are particularly suitable for estimating incidence of a disease.
Correct Answer: They are particularly suitable for estimating point prevalence.
Explanation:Cross-sectional studies aim to provide data about population health, normal ranges of biological parameters, and disease prevalence or severity by observing the entire population, or a representative subset, at a single point in time. Cross-sectional studies are relatively simple and quick to perform and can be used to study multiple outcomes, but are subject to confounding and recall bias and are not suitable for studying rare diseases. Cross-sectional studies cannot be used to assess causation or to consider trends over time.
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This question is part of the following fields:
- Evidence Based Medicine
- Study Methodology
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Question 2
Correct
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Glucagon may be used as an antidote for overdose with which of the following:
Your Answer: Beta blockers
Explanation:Glucagon is a peptide hormone that is produced and secreted by alpha cells of the islets of Langerhans, which are located in the endocrine portion of the pancreas. The main physiological role of glucagon is to stimulate hepatic glucose output, thereby leading to increases in glycaemia. It provides the major counter-regulatory mechanism to insulin in maintaining glucose homeostasis.
Hypoglycaemia is the principal stimulus for the secretion of glucagon but may also be used as an antidote in beta-blocker overdose and in anaphylaxis in patients on beta-blockers that fail to respond to adrenaline.
Glucagon then causes:
Glycogenolysis
Gluconeogenesis
Lipolysis in adipose tissue
The secretion of glucagon is also stimulated by:
Adrenaline
Cholecystokinin
Arginine
Alanine
Acetylcholine
The secretion of glucagon is inhibited by:
Insulin
Somatostatin
Increased free fatty acids
Increased urea productionGlycolysis is the metabolic pathway that converts glucose into pyruvate. The free energy released by this process is used to form ATP and NADH. Glycolysis is inhibited by glucagon, and glycolysis and gluconeogenesis are reciprocally regulated so that when one cell pathway is activated, the other is inactive and vice versa.
Glucagon has a minor effect of enhancing lipolysis in adipose tissue. Lipolysis is the breakdown of lipids and involves the hydrolysis of triglycerides into glycerol and free fatty acids. It makes fatty acids available for oxidation.
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This question is part of the following fields:
- Endocrine
- Pharmacology
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Question 3
Correct
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A 25-year-old patient requires procedural sedation for reduction of an open fracture of his tibia and fibula. You plan on using ketamine as the sedative agent.
Ketamine works as a result of action on what type of receptor? Select ONE answer only.Your Answer: N-methyl-D-aspartate (NMDA)
Explanation:Ketamine is the only anaesthetic agent available that has analgesic, hypnotic, and amnesic properties. When used correctly it is a very useful and versatile drug.
Ketamine acts by non-competitive antagonism of the NMDA receptor Ca2+ channel pore and also inhibits NMDA receptor activity by interaction with the phencyclidine binding site.
Ketamine can be used intravenously and intramuscularly. The intramuscular dose is 10 mg/kg, and when used by this route, it acts within 2-8 minutes and has a duration of action of 10-20 minutes. The intravenous dose is 1.5-2 mg/kg administered over a period of 60 seconds. When used intravenously, it acts within 30 seconds and has a duration of action of 5-10 minutes. Ketamine is also effective when administered orally, rectally, and nasally.
Ketamine causes tachycardia, an increase in blood pressure, central venous pressure, and cardiac output, secondary to an increase in sympathetic tone. Baroreceptor function is well maintained, and arrhythmias are uncommon.
The main disadvantage to the use of ketamine is the high incidence of hallucinations, nightmares, and other transient psychotic effects. These can be reduced by the co-administration of a benzodiazepine, such as diazepam or midazolam.
The main side effects of ketamine are:
Nausea and vomiting
Hypertension
Nystagmus
Diplopia
Rash -
This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 4
Correct
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A 29 year old woman is unable to invert her foot after sustaining an injury to her leg playing water-polo. Which of the following nerves are most likely damaged:
Your Answer: Tibial and deep fibular nerve
Explanation:Inversion of the foot is primarily produced by the tibialis anterior and the tibialis posterior muscles, innervated by the deep fibular nerve and the tibial nerve respectively.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 5
Correct
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A 27-year-old man presents with a laceration of his forearm that severed the nerve that innervates flexor carpi radialis.
Which of the following nerves has been damaged in this case? Select ONE answer only.Your Answer: The median nerve
Explanation:Flexor carpi radialis is innervated by the median nerve.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 6
Correct
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At rest, skeletal muscle accounts for between 15-20% of cardiac output and accounts for around 50% of body weight. This can increase to nearly 80% of cardiac output during exercise. Skeletal muscle circulation is highly controlled and has a number of specialized adaptations as a result of this high degree of disparity during exercise, in combination with the diversity in the size of skeletal muscle around the body.
What is the primary mechanism for boosting skeletal muscle blood flow during exercise?
Your Answer: Metabolic hyperaemia
Explanation:In skeletal muscle, blood flow is closely related to metabolic rate. Due to the contraction of precapillary sphincters, most capillaries are blocked off from the rest of the circulation at rest and are not perfused. This causes an increase in vascular tone and vessel constriction. As metabolic activity rises, this develops redundancy in the system, allowing it to cope with greater demand. During exercise, metabolic hyperaemia, which is induced by the release of K+, CO2, and adenosine, recruits capillaries. Sympathetic vasoconstriction in the active muscles is overridden by this. Simultaneously, blood flow in non-working muscles is restricted, preserving cardiac output. During exercise, muscle contractions pump blood through the venous system, raising the pressure differential between arterioles and venules and boosting blood flow via capillaries.
Capillary angiogenesis is evident when muscles are used repeatedly (e.g. endurance training). It is a long-term effect, not a quick fix for increased blood flow.
The local partial pressure of alveolar oxygen is the primary intrinsic control of pulmonary blood flow (pAO2). Low pAO2 promotes arteriole vasoconstriction and vice versa. The hypoxic pulmonary vasoconstriction (HPV) reflex allows blood flow to be diverted away from poorly ventilated alveoli and towards well-ventilated alveoli in order to maximize gaseous exchange.
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This question is part of the following fields:
- Cardiovascular Physiology
- Physiology
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Question 7
Correct
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Which of the following statements regarding forest plots is true? Select ONE answer only.
Which of the following statements regarding forest plots is true? Select ONE answer only.Your Answer: Larger studies are associated with smaller horizontal lines
Explanation:Forest plots are graphical displays designed to illustrate the relative strength of treatment effects in multiple individual studies addressing the same question.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 8
Correct
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At which vertebral level does the spinal cord normally end in adults?
Your Answer: L1/L2
Explanation:The spinal cord starts at the foramen magnum, where it is continuous with the medulla oblongata, which is the most caudal portion of the brainstem.
It then extends inferiorly through the vertebral canal. In adults, it usually ends at the level of the first or second lumbar vertebra.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 9
Incorrect
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A 66-year-old male was admitted from the Emergency Department due to severe pain in the left forearm and hand, refractory to pain medication along with pallor and hypothermia of the affected limb. Ultrasound doppler showed an arterial embolism. Circulation was restored after vascular surgery, but there was extensive, irreversible muscle damage.
How will the muscle heal from an injury of this type?Your Answer: Volkmann’s ischaemic contracture
Correct Answer: Diffuse formation of fibrous tissue
Explanation:Once muscle tissue is damaged, there will be healing via diffuse formation of fibrous tissue, especially due to the widespread ischemia.
Callus formation takes place in the healing of bone, not muscle.
Organised scar formation occurs when a lacerated wound is approximated by sutures so that primary intention wound healing can occur.
Liquefaction degeneration occurs following ischemia in the brain.
Volkmann’s ischemic contracture may occur, but it is not the primary type of healing that will take place but rather the effect of the fibrous scar formation.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 10
Incorrect
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Which of the following immunoglobulin molecules is the most abundant in secretions (such as saliva and breast milk):
Your Answer: IgG
Correct Answer: IgA
Explanation:IgA is the predominant antibody class in secretions and tremendous quantities are secreted into various body spaces and onto mucosal surfaces (the gut lumen, the pharynx and sinuses, the larger airways, although not the alveoli).
Because of its size, the majority of IgM is found in the circulation.Along with IgM, IgD is predominant among the surface receptors of mature B cells, where it plays a key role in B cells activation.
IgE has the lowest concentration in normal human serum. It plays a prominent role in immune responses to helminth parasites, and in allergic reactions.
IgG is the most abundant immunoglobulin and constitutes 75 percent of serum immunoglobulin in an adult human -
This question is part of the following fields:
- Immune Responses
- Pathology
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Question 11
Correct
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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: 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 12
Correct
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A 78-year-old man develops renal impairment and hearing loss after inpatient management for sepsis.
Which of these antibiotics is most likely to have been used?Your Answer: Gentamicin
Explanation:Gentamicin, an aminoglycoside antibiotic, acts by binding to the 30S subunit of the bacterial ribosome inhibiting the binding of aminoacyl-tRNA, and thus prevents initiation of protein synthesis.
Two of its most notable side effects are reversible nephrotoxicity(caused by the inhibition of protein synthesis in renal cells, which causes acute tubular necrosis) and hearing loss (caused by damage to the vestibular apparatus of the inner ear).
Both side effects are dose-related and occur commonly in the elderly.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 13
Correct
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Antidiuretic hormone (ADH) is synthesised by which of the following:
Your Answer: Hypothalamus
Explanation:Antidiuretic hormone is synthesised in the hypothalamus and transported to the posterior pituitary within nerve fibres where it is stored in secretory granules. ADH binds V2 receptors on renal principal cells in the late distal tubule and collecting ducts, raising cAMP levels and causing intracellular vesicles to fuse with the apical membrane. In their membrane these vesicles have water channels called aquaporins, which increase the water permeability allowing greater water reabsorption and concentration of urine. Excess levels of ADH results in syndrome of inappropriate ADH secretion (SIADH) characterised by hyponatremia with concomitant hypo-osmolality and high urine osmolality.
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 14
Incorrect
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Which of the following is NOT a typical side effect of thiopental sodium:
Your Answer: Involuntary muscle movements on induction
Correct Answer: Seizures
Explanation:Extravasation of thiopental during injection can lead to tissue damage. Accidental intra-arterial injection causes vasospasm and may lead to thrombosis and tissue necrosis. Other side effects include involuntary muscle movements on induction, cough and laryngospasm, arrhythmias, hypotension, headache and hypersensitivity reactions. Thiopental sodium has anticonvulsant properties and does not cause seizures.
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This question is part of the following fields:
- Anaesthesia
- Pharmacology
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Question 15
Correct
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A 66-year-old female with a history of stroke one year ago presents to the Family Medicine clinic complaining of fatigue, weight loss, and tongue discolouration. On examination, she seems malnourished, her tongue is beefy red, and an ataxic gait pattern is noticed.
Which ONE of the following conditions does this patient most likely have?Your Answer: Vitamin B12 deficiency
Explanation:A history of stroke and poor nutritional status points towards a nutritional deficiency as the most likely cause of her symptoms. The examination would differentiate between Vitamin B12 and Folic acid deficiency as in the former. The patient has a beefy red tongue and symptoms indicating peripheral nervous system involvement or subacute combined spinal cord degeneration. The patient may also have a lemon-yellow skin colour, loss of proprioception and vibratory sense and oral ulceration.
Investigations in B12 deficiency can reveal the following:
1. Macrocytic anaemia
2. Neutropoenia
3. Thrombocytopaenia
4. Blood film: anisocytosis, poikilocytosis
5. Low serum B12
6. Raised serum bilirubin (haemolysis)
7. Intrinsic factor antibodies
8. Positive Schilling test -
This question is part of the following fields:
- Haematology
- Pathology
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Question 16
Correct
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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: 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 17
Correct
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A patient suffers a stab wound to the neck. The entry point of the blade is situated within the posterior triangle of the neck.
Which of the following muscles is most likely to be involved? Select ONE answer only.Your Answer: Anterior scalene
Explanation:The anterior triangle is the triangular area of the neck found anteriorly to the sternocleidomastoid muscle. It is formed by the anterior border of sternocleidomastoid laterally, the median line of the neck medially and by the inferior border of the mandible superiorly. The apex of the anterior triangle extends towards the manubrium sterni. The anterior triangle contains:
Muscles: thyrohyoid, sternothyroid, sternohyoid muscles
Organs: thyroid gland, parathyroid glands, larynx, trachea, esophagus, submandibular gland, caudal part of the parotid gland
Arteries: superior and inferior thyroid, common carotid, external carotid, internal carotid artery (and sinus), facial, submental, lingual arteries
Veins: anterior jugular veins, internal jugular, common facial, lingual, superior thyroid, middle thyroid veins, facial vein, submental vein, lingual veins
Nerves: vagus nerve (CN X), hypoglossal nerve (CN XII), part of sympathetic trunk, mylohyoid nerveThe posterior triangle is a triangular area found posteriorly to the sternocleidomastoid muscle. It has three borders; anterior, posterior and inferior borders. The anterior border is the posterior margin of the sternocleidomastoid muscle. The posterior border is the anterior margin of the trapezius muscle, while the inferior border is the middle one-third of the clavicle. The investing layer of deep cervical fascia and integument forms the roof of the space, while the floor is covered with the prevertebral fascia along with levator scapulae, splenius capitis and the scalene muscles. The inferior belly of omohyoid subdivides the posterior triangle into a small supraclavicular, and a large occipital, triangle.
Contents:
Vessels: the third part of the subclavian artery, suprascapular and transverse cervical branches of the thyrocervical trunk, external jugular vein, lymph nodes
Nerves: accessory nerve (CN XI), the trunks of the brachial plexus, fibers of the cervical plexus
Of the muscles listed in the options, only the anterior scalene is situated within the posterior triangle of the neck. -
This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 18
Correct
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A 35-year-old man suffers an open fracture of his forearm. The nerve that innervates the pronator quadratus muscle is damaged as a consequence of this injury.
Which of the following nerves has been damaged in this case? Select ONE answer only.Your Answer: The anterior interosseous nerve
Explanation:Pronator quadratus is a small, square-shaped muscle that lies in the anterior compartment of the forearm. It arises from the distal fourth of the anterior surface of the ulna and inserts into the distal fourth of the anterior surface of the radius.
Pronator quadratus is innervated by the anterior interosseous nerve. It receives its blood supply from the anterior interosseous artery, which is a branch of the common interosseous artery, which in turn is a branch of the ulnar artery.
The main action of pronator quadratus is to assist pronator teres with pronation of the forearm. The deep fibres bind the radius and ulna together.
The pronator quadratus muscle highlighted in blue (adapted from Gray’s Anatomy) -
This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 19
Correct
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A 39-year-old guy comes to the emergency room with a persistent nasal bleed. You suspect the bleeding is coming from Little's area based on your examination. Which of the blood vessels listed below is most likely to be involved:
Your Answer: Sphenopalatine and superior labial arteries
Explanation:The Kiesselbach plexus is a vascular network formed by five arteries that supply oxygenated blood to the nasal septum, which refers to the wall separating the right and left sides of the nose. The five arteries that form the Kiesselbach plexus: the sphenopalatine artery, which branches from the maxillary artery originating behind the jawbone; the anterior ethmoidal artery, which branches from the ophthalmic artery behind the eye; the posterior ethmoidal artery, which also branches from the ophthalmic artery; the septal branch of the superior labial artery, which is a branch of the facial artery supplying blood to all of the superficial features of the face; and finally, the greater palatine artery, which is a terminal branch of the maxillary artery.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 20
Correct
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What is nimodipine used predominantly in the treatment of?
Your Answer: Prevention and treatment of vascular spasm following subarachnoid haemorrhage
Explanation:Nimodipine is a smooth muscle relaxant that is related to nifedipine, but the effects preferentially act on cerebral arteries. It is exclusively used for the prevention and treatment of vascular spasm after an aneurysmal subarachnoid haemorrhage.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 21
Correct
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A 23-year-old man is discovered to have an infection from Helicobacter pylori.
Which of the following types of cancer is mostly associated with Helicobacter pylori infection?Your Answer: Gastric cancer
Explanation:H. pylori is recognized as a major cause of type B gastritis, a chronic condition formerly associated primarily with stress and chemical irritants. In addition, the strong association between long-term H. pylori infection and gastric cancer has raised more questions regarding the clinical significance of this organism. There is speculation that long-term H. pylori infection resulting in chronic gastritis is an important risk factor for gastric carcinoma resulting in H. pylori being classified as a carcinogen.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 22
Incorrect
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Gastrin release from antral G-cells is stimulated by all but which one of the following:
Your Answer: Raised gastric pH
Correct Answer: Secretin
Explanation:Gastrin secretion is stimulated by:
The presence of small peptides and amino acids in chyme
Gastric distension
Vagal stimulation directly via acetylcholine and indirectly via gastrin-releasing peptide (GRP)
Raised gastric pH -
This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 23
Incorrect
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Which of the following statements is correct regarding anti-D immunoglobulin?
Your Answer: It is prepared from plasma taken from rhesus-positive individuals.
Correct Answer: It is administered as part of routine antenatal care for rhesus-negative mothers.
Explanation:In all non-sensitised pregnant women who are RhD-negative, it is recommended that routine antenatal anti-D prophylaxis is offered. Even if there is previous anti-D prophylaxis, use of routine antenatal anti-D prophylaxis should be given for a sensitising event early in the same pregnancy. Postpartum anti-D prophylaxis should also be given even if there has been previous routine antenatal anti-D prophylaxis or antenatal anti-D prophylaxis for a sensitising event in the same pregnancy.
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This question is part of the following fields:
- Immunoglobulins And Vaccines
- Pharmacology
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Question 24
Incorrect
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A 30-year-old man present to the ED with abdominal pain, nausea and vomiting. It has been present for the past two days.
Which of the following statements regarding diarrhoea and vomiting is true?
Your Answer: Cryptosporidia are susceptible to chlorine treatment
Correct Answer: E.Coli can cause diarrhoea and renal failure
Explanation:Escherichia coli strain 0157 causes enterohaemorrhagic diarrhoea and can lead to renal failure, haemolytic anaemia and thrombocytopenia.
Norwalk virus is an RNA virus.
Although transmission of rotavirus is primarily through the faeco-oral route, airborne spread has been seen in some cases.
Cryptosporidium are protozoa with acid fast walls and are resistant to both chlorine treatment and conventional filtering methods.
There is no therapy effective in treating cryptosporidium diarrhoea as the protozoa is not susceptible to antibiotics.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 25
Correct
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Regarding Clostridium species, which of the following statements is INCORRECT:
Your Answer: They are facultative anaerobes.
Explanation:Clostridium spp. are obligatory anaerobic spore-forming Gram-positive bacilli. Toxin production is the main pathogenicity mechanism.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 26
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: 100
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 27
Correct
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Regarding the abductor digiti minimi, which of the following statements is false?
Your Answer: It assists with flexion of the fifth finger at the middle phalanx
Explanation:Abductor digiti minimi is a short intrinsic muscle of the hand. It belongs to the group of muscles collectively called hypothenar muscles due to their acting on the 5th finger. Besides abductor digiti minimi, other hypothenar muscles include flexor digiti minimi brevis and opponens digiti minimi.
The main function of abductor digiti minimi involves abduction of the 5th finger, as well as flexion of its proximal phalanx. Along with other hypothenar muscles, this muscle forms the hypothenar eminence on the medial side of the palm.
Like other hypothenar muscles, abductor digiti minimi receives nervous supply from the deep branch of the ulnar nerve, derived from root values C8 and T1.
Abductor digiti minimi receives arterial blood supply from the palmar branch of ulnar artery, palmar digital artery, as well as branches of the ulnar side of the superficial palmar arch. The venous blood from the muscle is drained via the venous networks of the palm into the deep veins of the arm (vv. ulnares).
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 28
Correct
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All of the following statements are correct with regards to protection of the gastric mucosa except which of the following?
Your Answer: NSAIDs directly stimulate increased parietal cell acid production.
Explanation:Prostaglandin production, which usually inhibits acid secretion and increases mucus and bicarbonate secretion, is inhibited by NSAIDs.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 29
Incorrect
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On review of a patient's serum and urine osmolality test result, you note that both osmolarities are decreased. There urine osmolality does not increase with fluid ingestion.
What is the most likely cause?Your Answer: Alcohol ingestion
Correct Answer: Hyponatraemia
Explanation:As part of the investigation of hyponatraemia, serum osmolality is commonly requested in combination with urine osmolality to aid diagnosis.
When:
Serum osmolality is decreased and urine osmolality is decreased with no intake of fluid, the causes are
Hyponatraemia
Overhydration
Adrenocortical insufficiency
Sodium loss (diuretic or a low-salt diet)Serum osmolality is normal or increased and urine osmolality is increased the causes include:
Dehydration
Hyperkalaemia
Hyperglycaemia
Hyponatremia
Mannitol therapy
Diabetes mellitus
Alcohol ingestion
Congestive heart failure
Renal disease and uraemiaSerum osmolality is normal or increased and urine osmolality is decreased the usual cause is diabetes insipidus
Serum osmolality is decreased and urine osmolality is increased the usual cause is syndrome of inappropriate antidiuresis (SIAD)
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This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
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Question 30
Incorrect
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The movement of molecules across the cell membrane relies greatly on active transport.
Which of the following statements about active transport is correct?Your Answer: The proton pump is an example of secondary active transport
Correct Answer: Active transport occurs in glucose absorption from the gut
Explanation:The movement of a material against a concentration gradient, i.e. from a low to a high concentration, is known as active transport. Primary active transport is defined as active transport that involves the use of chemical energy, such as adenosine triphosphate (ATP). Secondary active transport occurs when an electrochemical gradient is used.
The sodium-potassium pump, calcium ATPase pump, and proton pump are all key active transport systems that use ATP. An electrochemical gradient is used by the sodium-calcium co-transporter, which is an example of secondary active transport.
The sodium-dependent hexose transporter SGLUT-1 transports glucose and galactose into enterocytes. Secondary active transport is exemplified here.
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This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
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Question 31
Correct
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A 4-year old boy is taken to the emergency room after a sudden onset of coughing and wheezing. Further investigation reveals that he was drawing quietly in his room, when suddenly, he became anxious and started coughing. The parents also noted that the eraser on top of the pencil was missing.
A plain radiographic chest imaging is conducted, and confirmed foreign body aspiration.
Which of the following areas in the tracheobronchial tree is the most probable location of the aspirated eraser?Your Answer: Right main bronchus
Explanation:In foreign body aspiration, the foreign body is more likely to enter the right main bronchus because it is shorter, wider and more vertical than the left main bronchus. In a patient who is standing or sitting, the foreign body tends to become lodged in the posterobasal segment of the inferior lobe of the right lung.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 32
Correct
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The following structures all lie anteriorly to the oesophagus EXCEPT for the:
Your Answer: Thoracic duct
Explanation:Posterior to the oesophagus, the thoracic duct is on the right side inferiorly but crosses to the left more superiorly (at T5).
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 33
Correct
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Depression of the eyeball is primarily produced by which of the following muscles:
Your Answer: Inferior rectus and superior oblique
Explanation:Depression of the eyeball is produced by the inferior rectus and the superior oblique muscles.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 34
Incorrect
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A 30-year-old male with a known allergy to natural latex rubber presents with an allergic reaction to a food he has just eaten.
Which ONE of these foods is most likely to cause an associated hypersensitivity in him?Your Answer: Potato
Correct Answer: Banana
Explanation:About one third of patients with allergy to natural latex rubber (NRL) have an associated allergy to some plant-derived foods. It is known as the latex-fruit syndrome and occurs commonly with consumption of fresh fruits. Banana and avocado are the most implicated fruits but it can also be seen with tomato, kiwi and chestnut.
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This question is part of the following fields:
- General Pathology
- Pathology
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Question 35
Correct
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Haemophilia B results from a deficiency in:
Your Answer: Factor IX
Explanation:Haemophilia B is a bleeding disorder caused by a deficiency of clotting factor IX. It is the second commonest form of haemophilia, and is rarer than haemophilia A. Haemophilia B tends to be similar to haemophilia A but less severe. The two disorders can only be distinguished by specific coagulation factor assays.
The incidence is one-fifth of that of haemophilia A. Laboratory findings demonstrate prolonged APTT, normal PT and low factor IX.
Haemophilia B inherited in an X-linked recessive fashion, affecting males born to carrier mothers.
There is also a variation called Leyden, in which factor IX levels are below 1% until puberty, when they rise, potentially reaching as high as 40-60% of normal. This is thought to be due to the effects of testosterone at puberty. -
This question is part of the following fields:
- Haematology
- Pathology
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Question 36
Correct
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Gastric emptying is inhibited by all of the following EXCEPT for:
Your Answer: Parasympathetic stimulation
Explanation:Gastric emptying is decreased by:
Enterogastric inhibitory reflexes stimulated by – Distension of the duodenum, The presence of fats in the duodenum (by stimulating release of cholecystokinin), A fall in the pH of chyme in the duodenum, An increase in the osmolality of chyme in the duodenum, Irritation of the mucosal lining of the duodenum, Hormones: Cholecystokinin, Secretin -
This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 37
Correct
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Digoxin is predominantly used for which of the following:
Your Answer: Rate control in persistent and permanent atrial fibrillation
Explanation:Digoxin is most useful for controlling the ventricular response in persistent and permanent atrial fibrillation and atrial flutter. Digoxin is usually only effective for controlling the ventricular rate at rest, and should therefore only be used as monotherapy in predominantly sedentary patients with non-paroxysmal atrial fibrillation. It is now rarely used for rapid control of heart rate, as even with intravenous administration, response may take many hours. Digoxin is reserved for patients with worsening or severe heart failure due to left ventricular systolic dysfunction refractory to combination therapy with first-line agents. Digoxin is contraindicated in supraventricular arrhythmias associated with accessory conduction pathways e.g. Wolff-Parkinson-White syndrome.
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This question is part of the following fields:
- Cardiovascular
- Pharmacology
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Question 38
Correct
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After collapsing at home, a 62-year-old man is transported in an ambulance. He is now awake, but he is experiencing palpitations and chest pain. He is rushed to resuscitation and placed on a cardiac monitor, which reveals ventricular tachycardia. An amiodarone infusion is set up.
Which of these statements about amiodarone is correct?Your Answer: It is expressed in breast milk
Explanation:Antiarrhythmic drug amiodarone is used to treat both ventricular and atrial arrhythmias. It’s a class III antiarrhythmic that works by prolonging the repolarization phase of the cardiac action potential, where potassium permeability is normally high and calcium permeability is low.
Dronedarone is sometimes used instead of amiodarone in certain situations. Although amiodarone is more effective than dronedarone, dronedarone has fewer side effects.
Grapefruit juice inhibits the metabolism of amiodarone.
The plasma half-life of amiodarone is very long, ranging from 2 weeks to 5 months. The half-life is about 2 months on average.
Because amiodarone is excreted in breast milk, it should be avoided by breastfeeding mothers. -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 39
Correct
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All of the following statements are considered true regarding nominal variables, except:
Your Answer: The central tendency of a nominal variable is given by its median
Explanation:A nominal variable is a type of variable that is used to name, label or categorize particular attributes that are being measured. It takes qualitative values representing different categories, and there is no intrinsic ordering of these categories.
A nominal variable is one of the 2 types of categorical variables and is the simplest among all the measurement variables. Some examples of nominal variables include gender, name, phone, etc.A nominal variable is qualitative, which means numbers are used here only to categorize or identify objects. They can also take quantitative values. However, these quantitative values do not have numeric properties. That is, arithmetic operations cannot be performed on them. If the variable is nominal, the mode is the only measure of central tendency to use.
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This question is part of the following fields:
- Evidence Based Medicine
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Question 40
Correct
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Fatigue, dizziness upon standing, muscle weakness, weight loss, nausea, and sweating are all symptoms that a patient may experience in Addison's disease.
Which of the following claims about Addison's disease is correct?Your Answer: ACTH levels are elevated in primary insufficiency
Explanation:The adrenal glands produce too little steroid hormones, which causes Addison’s disease. The production of glucocorticoids, mineralocorticoids, and sex steroids are all altered. The most prevalent cause is autoimmune adrenalitis, which accounts for 70-80 percent of cases.
It affects more women than males and occurs most frequently between the ages of 30 and 50.
The following are some of the clinical signs and symptoms of Addison’s disease:
Weakness and sluggishness
Hypotension is a condition in which the blood pressure (notably orthostatic hypotension)
Vomiting and nausea
Loss of weight
Axillary and pubic hair loss
Depression
Hyperpigmentation is a condition in which a person’s (palmar creases, buccal mucosa and exposed areas more commonly affected)
The following are the classic biochemical hallmarks of Addison’s disease:
Hyponatraemia
Hyperkalaemia
Hypercalcaemia
Hypoglycaemia
Acidosis metabolica
When ACTH levels are combined with cortisol levels, it is possible to distinguish between primary and secondary adrenal insufficiency:
In primary insufficiency, levels rise.
In secondary insufficiency, levels are low or low normal. -
This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 41
Correct
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A 23-year-old student presents to the emergency department with a terrible headache, photophobia, and a fever. On her lower limbs, you see a non-blanching purpuric rash. In the department, a lumbar puncture is conducted. What do you think you'll notice on Gram stain:
Your Answer: Gram negative diplococci
Explanation:Bacterial meningitis and septicaemia are most commonly caused by meningococcal bacteria. The Gram-negative diplococci Neisseria Meningitidis causes meningitis. Gram stain and culture of CSF identify the etiologic organism, N meningitidis. In bacterial meningitis, Gram stain is positive in 70-90% of untreated cases, and culture results are positive in as many as 80% of cases.
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This question is part of the following fields:
- Infections
- Microbiology
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Question 42
Incorrect
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Given a patient with dislocation of the patella, which muscle is the most important to address during rehabilitation to prevent recurrent dislocation?
Your Answer: Rectus femoris
Correct Answer: Vastus medialis
Explanation:Patellar dislocation is a disabling musculoskeletal disorder which predominantly affects younger people who are engaged in multidirectional physically active pursuits. Conservative (non-operative) treatment is the treatment of choice for FTPD (first time patellar dislocation). Quadriceps strengthening exercises are considered one of the principal management aims for people following FTPD. A United Kingdom (UK) survey of physiotherapy practice has shown that quadriceps strengthening and specific-vastus medialis obliquus (VMO) or distal vastus medialis (VM) muscle strengthening or recruitment exercises were two of the most frequently used interventions for this population. Specific VM exercises are favoured in some quarters based on the assumption that the VM has an important role in preventing excessive lateral patellar translation.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 43
Correct
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Thyroid cancer has spread to the regional lymph nodes of a patient as seen in a staging CT scan.
The lymph from the thyroid gland will drain directly to which of the following nodes?Your Answer: Deep lateral cervical lymph nodes
Explanation:Lymphatic drainage of the thyroid gland involves the lower deep cervical, prelaryngeal, pretracheal, and paratracheal nodes. The paratracheal and lower deep cervical nodes, specifically, receive lymphatic drainage from the isthmus and the inferior lateral lobes. The superior portions of the thyroid gland drain into the superior pretracheal and cervical nodes.
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This question is part of the following fields:
- Anatomy
- Head And Neck
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Question 44
Correct
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A 6-year-old female is brought to the Ophthalmology Clinic by her mother with the complaint of itching, redness, and a watery discharge of the right eye. Past medical history revealed an upper respiratory tract infection one week ago.
On examination of the right eye, there is mild erythema of the palpebral conjunctiva and visible follicles seen on eversion of the eyelid, lid oedema, and subconjunctival petechial haemorrhages. The discharge is watery and not purulent.
You diagnose her with viral conjunctivitis. According to the current NICE guidelines, which ONE of the following management options would NOT be included for this patient?Your Answer: The child should be excluded from school until the infection has resolved
Explanation:The NICE guidelines do NOT recommend isolating a patient with viral conjunctivitis from others or skipping school or work. The disease is contagious, but the spread of the disease can be controlled by maintaining good hygiene practices such as:
1. frequent hand washing
2. use of separate flannels and towels
3. Avoid close contact with othersAntibiotic prescriptions are not part of the NICE guidelines for viral conjunctivitis as they will not affect the course of the disease. Most cases of viral conjunctivitis are self-limiting and resolve within one to two weeks.
The NICE guidelines recommend that symptoms may be eased with self-care measures such as:
1. Bathing/cleaning the eyelids with cotton wool soaked in sterile saline or boiled and cooled water to remove any discharge
2. Cool compresses applied gently around the eye area
3. Use of lubricating drops or artificial tears -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 45
Incorrect
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Which of the following features of cell damage tends to be reversible:
Your Answer: Membrane blebs and holes
Correct Answer: Swelling of endoplasmic reticulum and some mitochondria
Explanation:Features of cell damage that tend to be reversible include: swelling of endoplasmic reticulum and some mitochondrialoss of ribosomescell stress response
Features of cell damage that tend to be irreversible include: loss of nucleolus, no ribosomes, swelling of all mitochondria, nuclear condensation, membrane blebs and holes, lysosome rupture, fragmentation of all inner membranes, nuclear breakup -
This question is part of the following fields:
- Inflammatory Responses
- Pathology
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Question 46
Correct
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A 45-year-old woman presents with persistent palpitations for the past two days. She has a good haemodynamic balance. An ECG is performed, which reveals that she has atrial flutter. The patient is examined by a cardiology registrar, who recommends using a 'rate control' strategy while she waits for cardioversion.
Which of the drugs listed below is the best fit for this strategy?Your Answer: Bisoprolol
Explanation:In atrial flutter, ventricular rate control is usually used as a stopgap measure until sinus rhythm can be restored. A beta-blocker (such as bisoprolol), diltiazem, or verapamil can be used to lower the heart rate.
Electrical cardioversion, pharmacological cardioversion, or catheter ablation can all be used to restore sinus rhythm. Cardioversion should not be attempted until the patient has been fully anticoagulated for at least three weeks if the duration of atrial flutter is unknown or has lasted for more than 48 hours. Emergency electrical cardioversion is the treatment of choice when there is an acute presentation with haemodynamic compromise. For the treatment of recurrent atrial flutter, catheter ablation is preferred.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 47
Incorrect
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Regarding linear relationships between two variables, what does a positive correlation coefficient indicate:
Your Answer: There is strong correlation between two variables
Correct Answer: The two variables are directly proportional
Explanation:A positive correlation coefficient means that the two variables are directly proportional e.g. height and weight in healthy growing children.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 48
Correct
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You are instructed by a senior to administer Mannitol to an RTA patient with increased intracranial pressure.
Mannitol is a low molecular weight compound that freely filters at the glomerulus and is not reabsorbed.
Out of the following, which is a contraindication to the use of mannitol?Your Answer: Severe pulmonary oedema
Explanation:Mannitol is the most widely used osmotic diuretic that is most commonly used to reduce cerebral oedema and intracranial pressure.
It is recommended to use mannitol for the reduction of CSF pressure/cerebral oedema in a dose of 0.25-2 g/kg as an intravenous infusion over 30-60 minutes. This can be repeated 1-2 times after 4-8 hours if needed.Mannitol has several contraindications and some of them are listed below:
1. Anuria due to renal disease
2. Acute intracranial bleeding (except during craniotomy)
3. Severe cardiac failure
4. Severe dehydration
5. Severe pulmonary oedema or congestion
6. Known hypersensitivity to mannitol -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 49
Correct
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In the small intestine, there is a deep gap between each villus that leads to the crypt of Lieberkühn, a tubular intestinal gland.
What is the primary function of these glands?
Your Answer: Production of an alkaline intestinal juice
Explanation:In the small intestine, there is a deep gap between each villus that leads to the crypt of Lieberkühn, a tubular intestinal gland. These glands create an alkaline intestinal juice that is a mixture of water and mucus with a pH of 7.4-7.8. Intestinal juice is released in a volume of 1-2 litres per day in response to distention of the small intestine or the irritating effects of chyme on the intestinal mucosa.
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This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 50
Incorrect
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Which of the following clinical features is a feature of a chronic extravascular haemolytic anaemia:
Your Answer: Raised serum conjugated bilirubin
Correct Answer: Gallstones
Explanation:Clinical features of haemolytic anaemia include:
Anaemia
Jaundice (caused by unconjugated bilirubin in plasma, bilirubin is absent from urine)
Pigment gallstones
Splenomegaly
Ankle ulcers
Expansion of marrow with, in children, bone expansion e.g. frontal bossing in beta-thalassaemia major
Aplastic crisis caused by parvovirus -
This question is part of the following fields:
- Haematology
- Pathology
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SESSION STATS - PERFORMANCE PER SPECIALTY
