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Question 1
Correct
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A 68-year-old man with multiple myeloma presents with complaints of abdominal pain and malaise. A series of blood tests is done and his calcium level is 2.96 mmol/l.What effect will this blood test result have on gastric secretions?
Your Answer: Stimulate the release of gastrin
Explanation:Hypercalcaemia stimulates the release of gastrin from the G-cells in the pyloric antrum of the stomach, the duodenum and the pancreas.Gastrin is also released in response to:Stomach distensionVagal stimulationThe presence of amino acids.Gastrin release is inhibited by the presence of acid and somatostatin.
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This question is part of the following fields:
- Gastrointestinal Physiology
- Physiology
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Question 2
Incorrect
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Which of the following is NOT mainly characterised by intravascular haemolysis:
Your Answer: Thrombotic thrombocytopenic purpura
Correct Answer: Beta-Thalassaemia
Explanation:Causes of intravascular haemolysis:Haemolytic transfusion reactionsG6PD deficiencyRed cell fragmentation syndromesSome severe autoimmune haemolytic anaemiasSome drug-and infection-induced haemolytic anaemiasParoxysmal nocturnal haemoglobinuria
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This question is part of the following fields:
- Haematology
- Pathology
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Question 3
Correct
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Cefotaxime (or ceftriaxone) is used first line for which of the following infections:
Your Answer: Blind treatment of suspected bacterial meningitis
Explanation:Cefotaxime (or ceftriaxone) are indicated first line in:- Blind treatment of meningitis in patients > 3 months (with amoxicillin if patient > 50 years)- Meningitis caused by meningococci- Meningitis caused by pneumococci- Meningitis caused by H. influenzae- Severe or invasive salmonellosis- Typhoid fever- Gonorrhoea- Gonococcal arthritis- Haemophilus influenzae epiglottitis
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 4
Correct
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A 6 year old boy is brought into the ED by his mom with a rash that is associated with Koplik's spots and a diagnosis of measles is made. What advice should be given about returning to school?
Your Answer: 4 days from the onset of the rash
Explanation:Prevention of spread of measles is extremely important and infected patients should be isolated. The infectious stage is from 3 days before the rash emerges and patients are advised to stay away from school/nursery/work for 4 days from onset of the rash.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 5
Incorrect
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A 33-year-old heavily muscled man presents with left-sided chest pain. After taking part in a powerlifting competition, he felt a painful snap at the front of his shoulder and chest. There is also the presence of bruising and swelling over the left side of his chest. A ruptured pectoralis major muscle was suspected upon examining the injured area. Which of the following statements regarding the surface markings of the pectoralis major muscle is considered correct?
Your Answer: The sternocostal head originates from the posterior surface of the sternum
Correct Answer: It inserts into the lateral lip of the bicipital groove of the humerus
Explanation:The pectoralis major is the superior most and largest muscle of the anterior chest wall. It is a thick, fan-shaped muscle that lies underneath the breast tissue and forms the anterior wall of the axilla.Its origin lies anterior surface of the medial half of the clavicle, the anterior surface of the sternum, the first 7 costal cartilages, the sternal end of the sixth rib, and the aponeurosis of the external oblique of the anterior abdominal wall.The insertion of the pectoralis major is at the lateral lip of the intertubercular sulcus of the humerus. There are 2 heads of the pectoralis major, the clavicular and the sternocostal, which reference their area of origin. The function of the pectoralis major is 3-fold and dependent on which heads of muscles are involved:- Flexion, adduction and medial rotation of the arm at the glenohumeral joint- Clavicular head causes flexion of the extended arm- Sternoclavicular head causes extension of the flexed armArterial supply of the pectoralis major, the pectoral artery, arises from the second branch of the axillary artery, the thoracoacromial trunk.The 2 heads of the pectoralis major have different nervous supplies. The clavicular head derives its nerve supply from the lateral pectoral nerve. The medial pectoral nerve innervates the sternocostal head. The lateral pectoral nerve arises directly from the lateral cord of the brachial plexus, and the medial pectoral nerve arises from the medial cord.
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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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The ECG of a patient presenting with a history of intermittent palpitations has a prolonged QT interval.Which of these can cause prolongation of the QT interval on the ECG?
Your Answer: Hypomagnesaemia
Explanation:The causes of a prolonged QT interval include:HypomagnesaemiaHypothermiaHypokalaemia HypocalcaemiaHypothyroidism Jervell-Lange-Nielsen syndrome (autosomal dominant)Romano Ward syndrome (autosomal recessive)Ischaemic heart diseaseMitral valve prolapseRheumatic carditisErythromycinAmiodaroneQuinidineTricyclic antidepressantsTerfenadineMethadoneProcainamideSotalol
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This question is part of the following fields:
- Cardiovascular Physiology
- Physiology
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Question 7
Incorrect
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About what percentage of filtered Na+is reabsorbed in the loop of Henle:
Your Answer: 30 - 40%
Correct Answer: 25%
Explanation:About 25% of filtered sodium is reabsorbed in the the loop of Henle.
Water-impermeable ascending loop of Henle plays a central role in maintaining salt-water balance by creating the cortico-medullary osmotic gradient to set up urinary concentrating ability and reabsorbing approximately 25% of the filtered NaCl load.
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This question is part of the following fields:
- Physiology
- Renal
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Question 8
Incorrect
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Which of the following statements is correct regarding gentamicin?
Your Answer: Gentamicin is effective against pneumococci.
Correct Answer: Gentamicin is ineffective against anaerobic bacteria.
Explanation:Gentamicin is the aminoglycoside of choice in the UK and is a parenterally administered, broad spectrum antibiotic typically used for moderate to severe gram negative infections. However, it is inactive against anaerobes. There is poor activity against haemolytic streptococci and pneumococci. It is usually given in conjunction with a penicillin or metronidazole (or both) when used for the blind treatment of undiagnosed serious infections. Nephrotoxicity and ototoxicity are the main toxic effects due to damage to the vestibulocochlear nerve (CN VIII).It is contraindicated in myasthenia gravis and should be used with great care in renal disease as it may result in accumulation and a higher risk of toxic side effects.
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 9
Incorrect
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Which of the following factors decreases insulin secretion:
Your Answer: Glucagon
Correct Answer: Catecholamines
Explanation:Factors that increase insulin secretion:↑ Blood glucose↑ Amino acids↑ Fatty acidsGlucagonSecretinAcetylcholineFactors that decrease insulin secretion:↓ Blood glucoseSomatostatinCatecholamines
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This question is part of the following fields:
- Endocrine
- Physiology
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Question 10
Incorrect
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A 58-year-old man showing symptoms of increase in weight, proximal muscular weakening and withering, easy bruising, and acne. You notice that he has a full, plethoric aspect to his face, as well as significant supraclavicular fat pads, when you examine him. His blood pressure is 158/942 mmHg, and his glucose tolerance has lately been impaired. His potassium level is 3.2 mmol/L.What is the MOST LIKELY diagnosis?
Your Answer: Addison’s disease
Correct Answer: Cushing’s syndrome
Explanation:Cushing’s syndrome is a group of symptoms and signs brought on by long-term exposure to high amounts of endogenous or exogenous glucocorticoids. Cushing’s syndrome affects about 10-15 persons per million, and it is more common in those who have had a history of obesity, hypertension, or diabetes.Cushing’s syndrome has a wide range of clinical manifestations that are dependent on the degree of cortisol overproduction. The appearance might be vague and the diagnosis difficult to detect when cortisol levels are just somewhat elevated. On the other hand, in long-term cases of severely increased cortisol levels, the presentation might be colourful and the diagnosis simple.Cushing’s syndrome has the following clinical features:Obesity and weight growth in the true senseSupraclavicular fat pads are fat pads that are located above the clavicle.Buffalo humpFullness and plethora of the face (‘moon facies’)Muscle atrophy and weakening at the proximal levelDiabetes mellitus, also known as impaired glucose toleranceHypertensionSkin thinning and bruisingDepressionHirsutismAcneOsteoporosisAmenorrhoea or oligomenorrhoeaCortisol levels fluctuate throughout the day, with the greatest levels occurring around 0900 hours and the lowest occurring at 2400 hrs during sleep. The diurnal swing of cortisol levels is lost in Cushing’s syndrome, and levels are greater during the whole 24-hour period. In the morning, levels may be normal, but they may be high at night-time, when they are generally repressed. As a result, random cortisol testing is not an effective screening technique and is not advised.The following are the two most common first-line screening tests:Cortisol levels in the urine are measured every 24 hours.A diagnosis of Cushing’s syndrome can be made if more than two collections measure cortisol excretion more than three times the upper limit of normal.Physical stress (e.g., excessive exercise, trauma), mental stress (e.g., sadness), alcohol or drug misuse, complex diabetes, and pregnancy can all cause false positives.Renal dysfunction, inadequate collection, and cyclical Cushing’s disease can all cause false negatives.The overnight low-dose dexamethasone suppression test (LDDST) involves giving 1 mg of dexamethasone at 11 p.m. and measuring blood cortisol levels at 8 a.m. the next day.Cushing’s syndrome is diagnosed when cortisol is not suppressed to less than 50 nmol/L.It might be difficult to tell the difference between mild Cushing’s disease and normal cortisol production.False positives can occur as a result of depression, severe systemic sickness, renal failure, prolonged alcohol misuse, old age, and the use of hepatic enzyme-inducing medicines, among other things.False negatives are extremely uncommon in Cushing’s disease patients.A characteristic biochemical picture might also be helpful in confirming the diagnosis of Cushing’s syndrome. The following are the primary characteristics:HypokalaemiaAlkalosis metabolique
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This question is part of the following fields:
- Endocrine Physiology
- Physiology
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Question 11
Incorrect
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Regarding the lung roots, which of the following statements is CORRECT:
Your Answer: The vagus nerves pass immediately anterior to the lung roots.
Correct Answer: Generally the pulmonary arteries lie superior to the pulmonary veins in the lung root.
Explanation:Each lung root contains a pulmonary artery, two pulmonary veins, a main bronchus, bronchial vessels, nerves and lymphatics. Generally the pulmonary artery is superior in the lung root, the pulmonary veins are inferior and the bronchi are somewhat posterior in position. The vagus nerves pass posterior to the lung roots while the phrenic nerves pass anterior to them.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 12
Correct
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A patient has a diagnosis of acute osteomyelitis. They have no joint prosthesis on indwelling metal work and no known drug allergies. He has had a recent skin swab that has cultured MRSA and MRSA infection is suspected.Which of the following antibacterial agents would be most appropriate to prescribe in this case? Select ONE answer only.
Your Answer: Vancomycin
Explanation:In the majority of patients the commonest causative organism for osteomyelitis isStaphylococcus aureus.Salmonella spp. are the commonest cause in patients with sickle cell disease.Other bacteria that can cause osteomyelitis include:Enterobacter spp.Group A and B streptococcusHaemophilus influenzaeThe current recommendations by NICE and the BNF on the treatment of osteomyelitis are:Flucloxacillin first-lineConsider adding fusidic acid or rifampicin for initial 2 weeksIf penicillin allergic use clindamycinIf MRSA is suspected use vancomycinSuggested duration of treatment is 6 weeks for acute infection
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 13
Incorrect
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A new test is being developed to diagnose chlamydia. 1000 people aged 15 – 35 years attending a GUM clinic undergo the new test and the current gold standard nucleic acid amplification test (NAAT) to confirm the diagnosis. Of the 1000 people, 250 are diagnosed with chlamydia. Of the patients diagnosed with chlamydia, 240 test positive with the new diagnostic test and of the patients not diagnosed with chlamydia, 150 test positive with the new diagnostic test. What is the negative predictive value of this test:Chlamydia YesChlamydia NoTotalPositive testa= 240b = 150390Negative testc = 10d = 600610Total2507501000
Your Answer: 0.62
Correct Answer: 0.98
Explanation:Negative predictive value (NPV) is the proportion of individuals with a negative test result who do not have the disease.Negative predictive value (NPV) = d/(c+d) = 600/610 = 0.98 = 98%This means there is a 98% chance, if the test is negative, that the patient does not have chlamydia.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 14
Incorrect
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Which law describes the rate of diffusion in a solution?
Your Answer: Starling’s law
Correct Answer: Fick’s law
Explanation:Fick’s law describes the rate of diffusion in a solution. Fick’s law states that:Jx = -D A (ΔC / Δx)Where:Jx = The amount of substance transferred per unit timeD = Diffusion coefficient of that particular substanceA = Surface area over which diffusion occursΔC = Concentration difference across the membraneΔx = Distance over which diffusion occursThe negative sign reflects movement down the concentration gradient
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This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
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Question 15
Incorrect
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Regarding the power of a study, which of the following statements is INCORRECT:
Your Answer: The power of a study is greater for a larger expected effect size.
Correct Answer: The power of a study is not affected by data variability.
Explanation:A study should only be undertaken if the power is at least 80%; a study power set at 80% accepts a likelihood of 1 in 5 (20%) of missing a statistically significant difference where one exists.The determinants of power are:the sample size (the power increases with sample size)the variability of the observations (the power increases as the variability decreases)the effect size of interest (the power is greater for a larger expected effect size)and the significance level, α (the power is greater if the significance level is larger); therefore the probability of a type I error increases as the probability of a type II error decreases.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 16
Incorrect
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You're evaluating a male patient who's having a lung function test done. In calculating the patient’s functional residual capacity, what parameters should you add to derive the functional residual capacity volume?
Your Answer: Residual volume + tidal volume
Correct Answer: Expiratory reserve volume + residual volume
Explanation:The volume of air that remains in the lungs after a single breath is known as functional residual capacity (FRC). It is calculated by combining the expiratory reserve volume and residual volume.
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This question is part of the following fields:
- Physiology
- Respiratory Physiology
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Question 17
Incorrect
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A 65-year-old man presents with a red, hot, swollen great toe. A diagnosis of acute gout is made. His past medical history includes heart failure and type 2 diabetes mellitus.Which of the following is the most appropriate medication to use in the treatment of his gout? Select ONE answer only.
Your Answer: Naproxen
Correct Answer: Colchicine
Explanation:In the absence of any contra-indications, high-dose NSAIDs are the first-line treatment for acute gout. Naproxen 750 mg as a stat dose followed by 250 mg TDS is a commonly used and effective regime.Aspirin should not be used in gout as it reduces the urinary clearance of urate and interferes with the action of uricosuric agents. Naproxen, Diclofenac or Indomethacin are more appropriate choices.Allopurinol is used prophylactically, preventing future attacks by reducing serum uric acid levels. It should not be started in the acute phase as it increases the severity and duration of symptoms.Colchicine acts on the neutrophils, binding to tubulin to prevent neutrophil migration into the joint. It is as effective as NSAIDs in relieving acute attacks. It also has a role in prophylactic treatment if Allopurinol is not tolerated.NSAIDs are contra-indicated in heart failure as they can cause fluid retention and congestive cardiac failure. Colchicine is the preferred treatment in patients with heart failure or those who are intolerant of NSAIDs.
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This question is part of the following fields:
- Musculoskeletal Pharmacology
- Pharmacology
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Question 18
Incorrect
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Bordetella pertussis causes which of the following infectious diseases:
Your Answer: Common cold
Correct Answer: Whooping cough
Explanation:Bordetella pertussis causes whooping cough. Acute bronchiolitis is typically caused by respiratory syncytial virus. Parainfluenza virus is the most common cause of croup. Acute epiglottitis is usually caused by an infection with Haemophilus influenzae type b (Hib) bacteria. The common cold may be caused by a number of viruses including rhinovirus and coronavirus.
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This question is part of the following fields:
- Microbiology
- Pathogens
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Question 19
Incorrect
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You are giving a teaching session to a group of final year medical students regarding lower limb neurology. Which of the following clinical features would be expected in an obturator nerve palsy:
Your Answer: Weakness of hip flexion
Correct Answer: Weakness of hip adduction
Explanation:Damage to the obturator nerve results in weak adduction of the hip with lateral swinging of the limb during walking due to unopposed abduction.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 20
Correct
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A 40-year-old woman presents with retrosternal central chest pain that she has been complaining about for the past two days. Upon deep inspiration and while lying flat, the pain worsens but relieved by sitting forwards. The pain radiates to both of her shoulders. The result of her ECG shows widespread concave ST-elevation and PR depression. A diagnosis of pericarditis is suspected. Which of the following nerves is responsible for the pattern of her pain?
Your Answer: Phrenic nerve
Explanation:Pericarditis is inflammation of the pericardial sac and is the most common pathologic process involving the pericardium. Frequently, pericardial inflammation can be accompanied by increased fluid accumulation within the pericardial sac forming a pericardial effusion, which may be serous, hemorrhagic or purulent depending on aetiology.The classic presentation is with chest pain that is central, severe, pleuritic (worse on deep inspiration) and positional (improved by sitting up and leaning forward). The pain may also be radiating and may involve the ridges of the trapezius muscle if the phrenic nerve is inflamed as it traverses the pericardium.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 21
Incorrect
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A 67-year-old woman arrives at the Emergency Department with chest pain. Flecainide is one of the medications she is taking.Which of the following statements about flecainide mechanism of action is correct?
Your Answer: Opens K + channels in the heart
Correct Answer: Blocks Na+ channels in the heart
Explanation:Flecainide is an antiarrhythmic drug of class Ic that works by blocking the Nav1.5 sodium channel in the heart, prolonging the cardiac action potential and slowing cardiac impulse conduction. It has a significant impact on accessory pathway conduction, particularly retrograde conduction, and significantly reduces ventricular ectopic foci.Many different arrhythmias can be treated with flecainide, including:Pre-excitation syndromes (e.g. Wolff-Parkinson-White)Acute atrial arrhythmiasVentricular arrhythmiasChronic neuropathic painThe use of flecainide is contraindicated in the following situations:Abnormal left ventricular functionAtrial conduction defects (unless pacing rescue available)Bundle branch block (unless pacing rescue available)Distal block (unless pacing rescue available)Haemodynamically significant valvular heart diseaseHeart failureHistory of myocardial infarctionLong-standing atrial fibrillation where conversion to sinus rhythm not attemptedSecond-degree or greater AV block (unless pacing rescue available)Sinus node dysfunction (unless pacing rescue available)Flecainide should only be used in people who don’t have a structural heart problem. The CAST trial found a significant increase in sudden cardiac death and all-cause mortality in patients with an ejection fraction of less than 40% after a myocardial infarction, where it tended to be pro-arrhythmic.Anti-arrhythmic drugs have a limited and ineffective role in the treatment of atrial flutter. It’s important to keep in mind that flecainide shouldn’t be used by itself to treat atrial flutter. When used alone, there is a risk of inducing 1:1 atrioventricular conduction, which results in an increase in ventricular rate that is paradoxical. As a result, it should be used in conjunction with a beta-blocker or a calcium channel blocker with a rate-limiting effect.
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This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
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Question 22
Correct
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A p value < 0.05 obtained from a study with a significance level (α) of 0.05, means all of the following, EXCEPT:
Your Answer: the result is clinically significant.
Explanation:A p value < 0.05:is statistically significantmeans that the probability of obtaining a given result by chance is less than 1 in 20means the null hypothesis is rejectedmeans there is evidence of an association between a variable and an outcomeNote that this does not tell us whether the result is clinically significant.
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This question is part of the following fields:
- Evidence Based Medicine
- Statistics
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Question 23
Incorrect
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A young patient presents with the features of an easily recognisable infectious disease.Which of the following infectious diseases typically has an incubation period of less than 1 week? Select ONE answer only.
Your Answer: Rubella
Correct Answer: Cholera
Explanation:Cholera has an incubation period of 12 hours to 6 days.Other infectious disease that have an incubation period of less than 1 week include:Staphylococcal enteritis (1-6 hours)Salmonella enteritis (12-24 hours)Botulism (18-36 hours)Gas gangrene (6 hours to 4 days)Scarlet fever (1-4 days)Diphtheria (2-5 days)Gonorrhoea (3-5 days)Yellow fever (3-6 days)Meningococcaemia (1-7 days)Brucellosis has an incubation period of 7-21 days.Measles has an incubation period of 14-18 days.Falciparum malaria usually has an incubation period of 7-14 days. The other forms of malaria have a longer incubation period of 12-40 days.Rubella has an incubation period of 14-21 days.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 24
Incorrect
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An elderly female has a bacterial infection and you are asked to prescribe an antibiotic to her. This antibiotic is a nucleic acid synthesis inhibitor.Which of the following antimicrobial drugs will be prescribed to this patient?
Your Answer: Erythromycin
Correct Answer: Metronidazole
Explanation:Metronidazole and the other 5-nitroimidazole agents inhibit nucleic acid synthesis by forming toxic free radical metabolites in the bacterial cell that damage DNA. Vancomycin inhibits cell wall peptidoglycan formation by binding the D-Ala-D-Ala portion of cell wall precursors. Erythromycin inhibits protein synthesis and blocks translocation by binding to the 23S rRNA of the 50S ribosomal subunit.Chloramphenicol blocks peptidyl transferase at 50S ribosomal subunit.Gentamicin, an aminoglycoside antibiotic, acts by binding to the 30S subunit of the bacterial ribosome inhibiting the binding of aminoacyl-tRNA and thus preventing initiation of protein synthesis.An overview of the different mechanisms of action of the various types of antimicrobial agents is shown below:1. Inhibition of cell wall synthesis- Penicillins- Cephalosporins- Vancomycin2. Disruption of cell membrane function- Polymyxins- Nystatin- Amphotericin B3. Inhibition of protein synthesis- Macrolides- Aminoglycosides- Tetracyclines- Chloramphenicol4. Inhibition of nucleic acid synthesis- Quinolones- Trimethoprim- 5-nitroimidazoles- Rifampicin5. Anti-metabolic activity- Sulphonamides- Isoniazid
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This question is part of the following fields:
- Infections
- Pharmacology
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Question 25
Incorrect
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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: Ascending palatine and ascending pharyngeal arteries
Correct 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 26
Incorrect
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The sensation produced by touching the arm with a vibrating tuning fork during a neurological examination is mediated by which of the following spinal tracts:
Your Answer: Anterior spinothalamic tract
Correct Answer: Posterior column
Explanation:Fine-touch, proprioception and vibration sensation are mediated by the posterior column-medial lemniscus pathway.
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This question is part of the following fields:
- Anatomy
- Central Nervous System
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Question 27
Incorrect
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A patient presents with a history of excessive thirst, urination and high fluid intake. His blood sugar is normal. You estimate his osmolarity as part of his work-up.Which of these equations can be used to estimate osmolarity?
Your Answer:
Correct Answer: 2 (Na + ) + 2 (K + ) + Glucose + Urea
Explanation:Osmolality and osmolarity are measurements of the solute concentration of a solution. Although the two terms are often used interchangeably, there are differences in the definitions, how they are calculated and the units of measurement used.Osmolarity, expressed as mmol/L, is an estimation of the osmolar concentration of plasma. It is proportional to the number of particles per litre of solution.Measured Na+, K+, urea and glucose concentrations are used to calculate the value indirectly.It is unreliable in pseudohyponatremia and hyperproteinaemia.The equations used to calculate osmolarity are:Osmolarity = 2 (Na+) + 2 (K+) + Glucose + Urea (all in mmol/L)OROsmolarity = 2 (Na+) + Glucose + Urea (all in mmol/L)Doubling of sodium accounts for the negative ions associated with sodium, and the exclusion of potassium approximately allows for the incomplete dissociation of sodium chloride.
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This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
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Question 28
Incorrect
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Regarding the flexor digitorum profundus muscle, which of the following is true?
Your Answer:
Correct Answer: The medial aspect of the muscle is innervated by the ulnar nerve
Explanation:Flexor digitorum profundus is a fusiform muscle located deep within the anterior (flexor) compartment of the forearm. Along with the flexor pollicis longus and pronator quadratus muscles, it comprises the deep flexor compartment of the forearm.Flexor digitorum profundus has a dual innervation:(1) The medial part of the muscle, that inserts to the fourth and fifth digits, is innervated by the ulnar nerve (C8-T1);(2) The lateral part, that inserts to the second and third digits, is innervated by the median nerve, via anterior interosseous branch (C8-T1).
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 29
Incorrect
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A 26-year-old woman is currently 9 weeks pregnant. Upon interview and history taking, she mentioned that she visited a friend whose child had just been diagnosed with slapped cheek disease.If the mother contracts an illness during pregnancy, which among the following is not known to cause fetal abnormalities?
Your Answer:
Correct Answer: Hepatitis A
Explanation:Hepatitis A usually doesn’t pose a special risk to a pregnant woman or her baby. Maternal infection doesn’t result in birth defects, and a mother typically doesn’t transmit the infection to her baby. HAV is almost always transmitted by the faecal-oral route and is usually acquired through close personal contact or via contaminated food.When a woman has chickenpox in the first 20 weeks of pregnancy, there is a 1 in 50 chance for the baby to develop a set of birth defects. This is called the congenital varicella syndrome. It includes scars, defects of muscle and bone, malformed and paralyzed limbs, small head size, blindness, seizures, and intellectual disability.TORCH Syndrome refers to infection of a developing foetus or newborn by any of a group of infectious agents. “TORCH” is an acronym meaning (T)toxoplasmosis, (O)ther Agents, (R)ubella (also known as German Measles), (C)ytomegalovirus, and (H)erpes Simplex.Infection with any of these agents may cause a constellation of similar symptoms in affected newborns. These may include fever; difficulties feeding; small areas of bleeding under the skin, causing the appearance of small reddish or purplish spots; enlargement of the liver and spleen (hepatosplenomegaly); yellowish discoloration of the skin, whites of the eyes, and mucous membranes (jaundice); hearing impairment; abnormalities of the eyes; and other symptoms and findings.
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This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
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Question 30
Incorrect
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A 64-year-old lady attends the emergency department with a known brain tumour. Her left eye is directed outwards and downwards, she can't open it, and her pupil is fixed and dilated. The tumour is most likely compressing which of the following structures:
Your Answer:
Correct Answer: Oculomotor nerve
Explanation:The oculomotor nerve is the third cranial nerve. It is the main source of innervation to the extraocular muscles and also contains parasympathetic fibres which relay in the ciliary ganglion. Damage to the third cranial nerve may cause diplopia, pupil mydriasis, and/or upper eyelid ptosis. The clinical manifestations of third cranial nerve dysfunction reflect its constituent parts.
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This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
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SESSION STATS - PERFORMANCE PER SPECIALTY
