-
Question 1
Incorrect
-
Haemophilia B results from a deficiency in:
Your Answer: Factor VIII
Correct 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
-
-
Question 2
Correct
-
What is the main mechanism of action of dopamine as an inotropic sympathomimetic:
Your Answer: Beta1-receptor agonist
Explanation:Dopamine is a neurotransmitter and a metabolic precursor of the catecholamines. It acts on beta1-receptors in cardiac muscle increasing cardiac contractility, and increases renal perfusion by stimulating dopamine receptors in the renal vasculature. This is of benefit in cardiogenic shock where deterioration of renal function is common.
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 3
Incorrect
-
A 29-year-old woman with a skin infection not responding to first-line antibiotics return for a review clinic appointment. The result of her culture shows growth of methicillin-resistant Staphylococcus aureus (MRSA).
Which among the following antibiotics is methicillin-resistant Staphylococcus aureus usually sensitive to?Your Answer:
Correct Answer: Linezolid
Explanation:Historically, MRSA has been treated successfully with outpatient oral sulphonamides, clindamycin, rifampin, doxycycline, or a combination of these agents. With the development of increasing drug resistance of MRSA to these traditional antimicrobials, there has been a search for more effective antibiotics. One recent study demonstrated that vancomycin, linezolid, and quinupristin-dalfopristin were the most effective antibiotics against multiple strains of MRSA.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 4
Incorrect
-
The following statements about leukotrienes as chemical mediators of the acute inflammatory response are all true EXCEPT?
Your Answer:
Correct Answer: They decrease vascular permeability
Explanation:Leukotrienes increases (not decrease) vascular permeability during acute inflammation.
All the other statements are correct
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 5
Incorrect
-
Which of the following does NOT increase free ionised calcium levels:
Your Answer:
Correct Answer: Calcitonin
Explanation:Calcium homeostasis is primarily controlled by three hormones: parathyroid hormone, activated vitamin D and calcitonin.
Parathyroid hormone acts on the kidneys to increase calcium reabsorption in the distal tubule by activating Ca2+entry channels in the apical membrane and the Ca2+ATPase pump in the basolateral membrane (and to decrease phosphate reabsorption in the proximal tubule).
Activated vitamin D acts to increase calcium reabsorption in the distal tubule via activation of a basolateral Ca2+ATPase pump (and to increase phosphate reabsorption).
Calcitonin acts to inhibit renal reabsorption of calcium (and phosphate).
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 6
Incorrect
-
A newborn baby is rushed to the neonatal ICU 4 hours after birth due to sudden onset severe jaundice and generalised oedema. Family history reveals that this is the second baby, while blood testing shows that the mother has an Rh-negative blood group while the baby is Rh-positive. A diagnosis of haemolytic disease of the newborn is established.
Which one of the following hypersensitivity reactions have occurred in this case?Your Answer:
Correct Answer: Type II hypersensitivity reaction
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)oxoplasmosis, (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. -
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 7
Incorrect
-
Common causes of exudates are infection, pericarditis, and malignancy.
Which one statement about exudates is true?Your Answer:
Correct Answer: LDH levels are usually high
Explanation:An exudate is an inflammatory fluid emanating from the intravascular space due to changes in the permeability of the surrounding microcirculation.
Exudates are cloudy. It has high LDH levels, serum protein ratio >0.5, protein content >2.9g/dl, specific gravity of >1.020 and a serum-ascites albumin gradient (SAAG) of <1.2g/dl.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 8
Incorrect
-
A 59-year-old woman presents with a history of tiredness and weight gain and a diagnosis of hypothyroidism is suspected.
Which of these changes is likely to appear first in primary hypothyroidism?Your Answer:
Correct Answer: Increased thyroid-stimulating hormone (TSH)
Explanation:The earliest biochemical change seen in hypothyroidism is an increase in thyroid-stimulating hormone (TSH) levels.
Triiodothyronine (T3) and thyroxine (T4) levels are normal in the early stages.
TBG levels are generally unchanged in primary hypothyroidism.
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 9
Incorrect
-
During swallowing, which of the following structures primarily closes the tracheal opening:
Your Answer:
Correct Answer: Epiglottis
Explanation:The vocal cords of the larynx are strongly
approximated, and the larynx is pulled upward
and anteriorly by the neck muscles. These actions,
combined with the presence of ligaments that
prevent upward movement of the epiglottis, cause
the epiglottis to swing back over the opening
of the larynx. All these effects acting together
prevent the passage of food into the nose and
trachea. Most essential is the tight approximation
of the vocal cords, but the epiglottis helps to
prevent food from ever getting as far as the vocal
cords. Destruction of the vocal cords or of the
muscles that approximate them can cause
strangulation. -
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 10
Incorrect
-
A patient is diagnosed as having a glucagonoma. Her blood serum glucagon concentration is 1246 pg/mL.
Glucagon is produced in which of the following cells? Select ONE answer only.Your Answer:
Correct Answer: Alpha-cells in the pancreas
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.
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 11
Incorrect
-
The most important nerves for inversion of the foot are:
Your Answer:
Correct Answer: Tibial and deep fibular nerve
Explanation:Inversion of the foot is achieved by the tibialis anterior which is innervated by the deep fibular nerves, and the tibialis posterior muscles which is innervated by the tibial nerve respectively.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 12
Incorrect
-
A 66-year-old female who is a known case of atrial fibrillation comes to the Emergency Department with the complaint of fever and vomiting for the past two days. When her medical chart is reviewed, you see that she takes Warfarin for her arrhythmia.
Which ONE of the following medications cannot be prescribed to this patient?Your Answer:
Correct Answer: Ibuprofen
Explanation:Like other non-steroidal anti-inflammatory drugs, Ibuprofen cannot be given with Warfarin as it would increase the bleeding risk of this patient.
-
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 13
Incorrect
-
Regarding airway resistance, which of the following statements is CORRECT:
Your Answer:
Correct Answer: Airway resistance is predominantly determined by the radius of the airway as described by Poiseuille's law.
Explanation:Flow through airways is described by Darcy’s law which states that flow is directly proportional to the mouth-alveolar pressure gradient and inversely proportional to airway resistance. Airway resistance is primarily determined by the airway radius according to Poiseuille’s law, and whether the flow is laminar or turbulent. Parasympathetic stimulation causes bronchoconstriction and sympathetic stimulation causes bronchodilation, but mediated by beta2-adrenoceptors. Muscarinic antagonists e.g. ipratropium bromide cause bronchodilation.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 14
Incorrect
-
A 24-year-old patient is suspected to have a possible acute hepatitis B infection and is currently under investigation.
Which of the following markers is considered the earliest indicator of acute infection in acute Hepatitis B?Your Answer:
Correct Answer: Hepatitis B surface Ag
Explanation:HBsAg is the serological hallmark of HBV infection. After an acute exposure to HBV, HBsAg appears in serum within 1 to 10 weeks. Persistence of this marker for more than 6 months implies chronic HBV infection.
Anti-HBs is known as a neutralizing antibody, and confers long-term immunity. In patients with acquired immunity through vaccination, anti-HBs is the only serological marker detected in serum.
HBcAg is an intracellular presence in infected hepatocyte, thus it is not identified in the serum. During acute infection, anti-HBc IgM and IgG emerges 1–2 weeks after the presence of HBsAg along with raised serum aminotransferase and symptoms. After 6 months of acute infection, anti-HBc IgM wears off. Anti-HBc IgG continues to detect in both patients with resolved HBV infection and chronic hepatitis B.
Hepatitis D virus, also known as the delta hepatitis virus, is a defective ssRNA virus that requires HBV for replication. The infection can occur in one of two clinical forms, co-infection or superinfection. In a co-infection, the patient is simultaneously infected with HBV and HDV. In a superinfection, an HDV infection develops in a patient with a chronic HBV infection.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 15
Incorrect
-
Vitamin D is a group of secosteroids that play a role in calcium and phosphate control. Vitamin D's hormonally active metabolite is 1,25-dihydroxycholecalciferol.
Which of the following actions of 1,25-dihydroxycholecalciferol is a direct action?Your Answer:
Correct Answer: Increases renal phosphate reabsorption
Explanation:The hormone-active metabolite of vitamin D is 1,25-dihydroxycholecalciferol (commonly known as calcitriol). Its activities raise calcium and phosphate levels in the bloodstream.
The following are the primary effects of 1,25-dihydroxycholecalciferol:
Calcium and phosphate absorption in the small intestine is increased.
Calcium reabsorption in the kidneys is increased.
Increases phosphate reabsorption in the kidneys.
Increases the action of osteoclastic bacteria (increasing calcium and phosphate resorption from bone)
Inhibits the action of 1-alpha-hydroxylase in the kidneys (negative feedback)
Thyroid hormone (parathyroid hormone) Calcium reabsorption in the tubules of the kidneys is increased, but renal phosphate reabsorption is decreased. -
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 16
Incorrect
-
You have been asked to give a tutorial on common upper limb neurology to a group of medical students. You use the example of a man falling from a balcony onto spiked fencing, sustaining a puncture wound to the axilla. This results in an injury to the musculocutaneous nerve. Which of the following clinical features would you LEAST expect to see in this patient:
Your Answer:
Correct Answer: Weakness of forearm pronation
Explanation:Flexion of the arm and flexion and supination of the forearm are weakened but not lost entirely due to the actions of the pectoralis major and deltoid, the brachioradialis and the supinator muscles respectively. There is loss of sensation over the lateral aspect of the forearm. Forearm pronation would not be affected as this is primarily produced by the pronator quadratus and pronator teres muscles, innervated by the median nerve.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 17
Incorrect
-
A 67-year-old woman complains of general malaise, nausea, and vomiting. She is perplexed and declares that everything 'looks yellow.' Her potassium level is 6.8 mmol/l, according to a blood test.
Which of the drugs listed below is most likely to be the cause of her symptoms?Your Answer:
Correct Answer: Digoxin
Explanation:Because digoxin has a narrow therapeutic index, it can cause toxicity both during long-term therapy and after an overdose. Even when the serum digoxin concentration is within the therapeutic range, it can happen.
Acute digoxin toxicity usually manifests itself within 2-4 hours of an overdose, with serum levels peaking around 6 hours after ingestion and life-threatening cardiovascular complications following 8-12 hours.
Chronic digoxin toxicity is most common in the elderly or those with impaired renal function, and it is often caused by a coexisting illness. The clinical signs and symptoms usually appear gradually over days to weeks.
The following are characteristics of digoxin toxicity:
Nausea and vomiting
Diarrhoea
Abdominal pain
Confusion
Tachyarrhythmias or bradyarrhythmias
Xanthopsia (yellow-green vision)
Hyperkalaemia (early sign of significant toxicity)Some precipitating factors are as follows:
Elderly patients
Renal failure
Myocardial ischaemia
Hypokalaemia
Hypomagnesaemia
Hypercalcaemia
Hypernatraemia
Acidosis
Hypothyroidism
Spironolactone
Amiodarone
Quinidine
Verapamil
Diltiazem -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 18
Incorrect
-
An 18-year-old patient was brought to the ER after falling off of his skateboard. He is unable to flex the distal interphalangeal joint of his index finger. You suspect that he suffers from a supracondylar fracture. Which of the following conditions would confirm supracondylar fracture?
Your Answer:
Correct Answer: Inability to oppose the thumb
Explanation:A supracondylar fracture is a fracture that occurs through the thin section of the distal humerus above the growth plate.
A supracondylar fracture is most usually associated with median nerve injury. A medial nerve damage causes paralysis of the thenar muscles, as well as loss of thumb opposition.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 19
Incorrect
-
EMLA cream is a topical local anaesthetic containing which of the following:
Your Answer:
Correct Answer: 50/50 mixture 2.5% lidocaine and 2.5% prilocaine
Explanation:EMLA cream, an effective topical local anaesthetic, is a 50/50 mixture of 2.5% prilocaine and 2.5% lidocaine.
-
This question is part of the following fields:
- Anaesthesia
- Pharmacology
-
-
Question 20
Incorrect
-
A 50-year-old man presents with signs and symptoms of an anaphylactic reaction. His GP had recently given him a new medication.
Which one of these is the most likely medication responsible for the drug-induced anaphylactic reaction?
Your Answer:
Correct Answer: Penicillin
Explanation:The most common cause of drug-induced anaphylaxis is penicillin.
The second commonest cause are NSAIDs. Other drugs associated with anaphylaxis are ACE inhibitors and aspirin.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 21
Incorrect
-
Elevation of the eyeball is primarily produced by which of the following muscles:
Your Answer:
Correct Answer: Superior rectus and inferior oblique
Explanation:Elevation of the eyeball is produced by the superior rectus and the inferior oblique muscles.
-
This question is part of the following fields:
- Anatomy
- Head And Neck
-
-
Question 22
Incorrect
-
Foetal haemoglobin (HbF) comprises about how much of the total haemoglobin in adults:
Your Answer:
Correct Answer: 0.5 - 0.8%
Explanation:Foetal haemoglobin (HbF) makes up about 0.5 – 0.8 % of total adult haemoglobin and consists of two α and two gamma (γ) globin chains.
-
This question is part of the following fields:
- Basic Cellular
- Physiology
-
-
Question 23
Incorrect
-
Polyuria and polydipsia develop in a patient with a history of affective disorder, who has been on long-term lithium treatment. She has a fluid deprivation test done because she is suspected of having nephrogenic diabetic insipidus. Which of the following urine osmolality findings would be the most reliable in confirming the diagnosis?
Your Answer:
Correct Answer: After fluid deprivation <300 mosmol/kg, after IM desmopressin >800 mosmol/kg
Explanation:The inability to produce concentrated urine is a symptom of diabetes insipidus. Excessive thirst, polyuria, and polydipsia are all symptoms of this condition. There are two forms of diabetes insipidus: Nephrogenic diabetes insipidus and cranial (central) diabetes insipidus.
A lack of ADH causes cranial diabetic insipidus. Patients with cranial diabetes insipidus can have a urine output of up to 10-15 litres per 24 hours, however most patients can maintain normonatraemia with proper fluid consumption. Thirty percent of cases are idiopathic, while another thirty percent are caused by head injuries. Neurosurgery, brain tumours, meningitis, granulomatous disease (e.g. sarcoidosis), and medicines like naloxone and phenytoin are among the other reasons. There is also a very rare hereditary type that is linked to diabetes, optic atrophy, nerve deafness, and bladder atonia.
Renal resistance to the action of ADH causes nephrogenic diabetes insipidus. Urine output is significantly increased, as it is in cranial diabetes insipidus. Secondary polydipsia can keep serum sodium levels stable or raise them. Chronic renal dysfunction, metabolic diseases (e.g., hypercalcaemia and hypokalaemia), and medications, such as long-term lithium use and demeclocycline, are all causes of nephrogenic diabetes insipidus.
The best test to establish if a patient has diabetes insipidus vs another cause of polydipsia is the water deprivation test, commonly known as the fluid deprivation test. It also aids in the distinction between cranial and nephrogenic diabetes insipidus. Weight, urine volume, urine osmolality, and serum osmolality are all measured after patients are denied water for up to 8 hours. At the end of the 8-hour period, 2 micrograms of IM desmopressin is given, and measures are taken again at 16 hours.
The following are the way results are interpreted:
Urine osmolality after fluid deprivation : Urine osmolality after IM desmopressin
Cranial diabetes insipidus: <300 mosmol/kg : >800 mosmol/kg
Nephrogenic diabetes insipidus: <300 mosmol/kg : <300 mosmol/kg
Primary polydipsia: >800 mosmol/kg : >800 mosmol/kg -
This question is part of the following fields:
- Physiology
- Renal Physiology
-
-
Question 24
Incorrect
-
All of the following are indications for beta-blockers EXCEPT for:
Your Answer:
Correct Answer: Raynaud's disease
Explanation:Beta-blockers are contraindicated in Raynaud’s syndrome.
Beta-blockers may be indicated in:
Hypertension
Pheochromocytoma (only with an alpha-blocker)
Angina
Secondary prevention after ACS
Arrhythmias including atrial fibrillation
Heart failure
Thyrotoxicosis
Anxiety
Prophylaxis of migraine
Essential tremor
Glaucoma -
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 25
Incorrect
-
A 28-year-old known intravenous drug user has a history of persistent high-fever. On examination you hear a harsh systolic murmur and the patient says a murmur has never been heard before in previous hospital visits. A diagnosis of endocarditis is suspect.
Which of these antibacterial agents would be most appropriate to prescribe in this case?Your Answer:
Correct Answer: Flucloxacillin and gentamicin
Explanation:Endocarditis is infective or non infective inflammation (marantic endocarditis) of the inner layer of the heart and it often involves the heart valves.
Risk factors include:
Prosthetic heart valves
Congenital heart defects
Prior history of endocarditis
Rheumatic fever
Illicit intravenous drug useIn the presentation of endocarditis, the following triad is often quoted:
Persistent fever
Embolic phenomena
New or changing murmurFlucloxacillin and gentamicin are current recommended by NICE and the BNF for the initial ‘blind’ therapy in endocarditis.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 26
Incorrect
-
Which among the following antibacterial regimens is considered the most appropriate to prescribe in a patient presenting with clinical signs and symptoms consistent with a diagnosis of pelvic inflammatory disease?
Your Answer:
Correct Answer: Ceftriaxone plus doxycycline plus metronidazole
Explanation:The endocervix is the most common site of Neisseria gonorrhoeae infection in women. Symptoms of infection, when present, include dysuria, cervical discharge, and lower abdominal pain. However, 50% of cases in women may be asymptomatic leading to complications such as pelvic inflammatory disease (PID), which may cause sterility, ectopic pregnancy, or perihepatitis.
PID is also known as Fitz-Hugh-Curtis syndrome is defined as an inflammation of the upper genital tract due to an infection in women. The disease affects the uterus, fallopian tubes, and ovaries. It is typically an ascending infection, spreading from the lower genital tract.
The recommended intramuscular or oral regimens for PID are as follows:
Ceftriaxone at 500 mg IM in a single dose (for persons weighing ≥150 kg, administer 1 g of ceftriaxone); plus doxycycline at 100 mg PO BID for 14 days with metronidazole at 500 mg PO BID for 14 days.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 27
Incorrect
-
A 28-year-old woman with history of blunt thoracic trauma develops hypotension chest pain, and breathlessness. A bedside echocardiogram was performed and revealed a large pericardial effusion. Due to this finding, a pericardiocentesis was to be performed.
Which of the following statements is considered true regarding pericardiocentesis?Your Answer:
Correct Answer: The needle should be aimed at the midpoint of the left clavicle
Explanation:Pericardiocentesis is a procedure done to remove fluid build-up in the sac around the heart known as the pericardium. The pericardium can be tapped from almost any reasonable location on the chest wall. However, for the usual blind pericardiocentesis, the subxiphoid approach is preferred. Ideally, 2-D echocardiography is used to guide needle insertion and the subsequent path of the needle/catheter.
In the subxiphoid approach, the needle is inserted 1 cm inferior to the left xiphocostal angle with an angle of 30 degrees from the patient’s chest with a direction towards the left mid-clavicle.
The fingers may sense a distinct give when the needle penetrates the parietal pericardium. Successful removal of fluid confirms the needle’s position.
-
This question is part of the following fields:
- Anatomy
- Thorax
-
-
Question 28
Incorrect
-
Regarding Clostridium tetani, which of the following statements is CORRECT:
Your Answer:
Correct Answer: Metronidazole is usually the antibiotic of choice for tetanus infection.
Explanation:Clostridium tetani infection is predominantly derived from animal faeces and soil. Clostridium tetani has exotoxin-mediated effects, predominantly by tetanospasmin which inhibits the release of GABA at the presynaptic membrane throughout the central and peripheral nervous system. Metronidazole has overtaken penicillin as the antibiotic of choice for treatment of tetanus (together with surgical debridement, tetanus toxoid immunisation, and human tetanus immunoglobulin).
-
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 29
Incorrect
-
Which of these increases osteoclast activity?
Your Answer:
Correct Answer: Parathyroid hormone
Explanation:Osteoclasts are bone cell that break down bone tissue.
Parathyroid hormone increases osteoclastic activity.
1,25-dihydroxycholecalciferol increases osteoclastic activity
Calcitonin inhibits osteoclastic activity
Bisphosphonates are osteoclast inhibitors.
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 30
Incorrect
-
Regarding postural hypotension, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: Postural hypotension usually causes a reflex bradycardia.
Explanation:On standing from a prone position, gravity causes blood to pool in veins in the legs. Central venous pressure (CVP) falls, causing a fall in stroke volume and cardiac output (due to Starling’s law) and thus a fall in blood pressure. Normally this fall in BP is rapidly corrected by the baroreceptor reflex which causes venoconstriction (partially restoring CVP), and an increase in heart rate and contractility, so restoring cardiac output and blood pressure. Impaired autonomic nervous activity in the elderly accounts for the greater likelihood of postural hypotension. Any symptoms of dizziness, blurred vision or syncope is due to a transient fall in cerebral perfusion that occurs before cardiac output and mean arterial pressure (MAP) can be corrected.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 31
Incorrect
-
Question 32
Incorrect
-
For which of the following is micelle formation necessary to facilitate intestinal absorption?
Your Answer:
Correct Answer: Vitamin D
Explanation:The arrangement of micelles is such that hydrophobic lipid molecules lie in the centre, surrounded by hydrophilic bile acids that are arranged in the outer region. This arrangement allows the entry of micelles into the aqueous layers surrounding the microvilli. As a result, the products of fat digestion (fatty acids and monoglycerides), cholesterol and fat-soluble vitamins (such as vitamin D) can then diffuse passively into the enterocytes. The bile salts are left within the lumen of the gut where they are reabsorbed from the ileum or excreted in faeces.
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 33
Incorrect
-
While on morning rounds in the medical ward, the attending physician asks a medical student about the differences between transudates and exudates and their causes. The student explains that a transudate is an excess fluid that leaks out of an intravascular compartment due to an imbalance between oncotic and hydrostatic pressures.
Which ONE of the following conditions will he mention as the cause of a transudate?Your Answer:
Correct Answer: Meig’s syndrome
Explanation:Transudative effusions are caused due to systemic causes leading to increased hydrostatic pressure or decreased oncotic pressure. These include:
1) Meig’s Syndrome (Ovarian tumour causing ascites and pleural effusion)
2) Congestive heart failure
3) Nephrotic Syndrome
4) Myxoedema
5) Cirrhosis
6) SarcoidosisAn exudate is caused by local inflammation and results from increased vascular permeability. Causes include:
1) Rheumatoid arthritis
2) Pneumonia leading to empyema
3) Malignancies
4) Pericarditis -
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 34
Incorrect
-
Which of the following is NOT a function of the commensal intestinal bacterial flora:
Your Answer:
Correct Answer: Breakdown of haem into bilirubin
Explanation:Commensal intestinal bacterial flora have a role in:Keeping pathogenic bacteria at bay by competing for space and nutrientConverting conjugated bilirubin to urobilinogen (some of which is reabsorbed and excreted in urine) and stercobilinogen which is excreted in the faecesThe synthesis of vitamins K, B12, thiamine and riboflavinThe breakdown of primary bile acids to secondary bile acidsThe breakdown of cholesterol, some food additives and drugs
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 35
Incorrect
-
A 50-year-old woman has an anaphylactic reaction following accidental ingestion peanuts at a restaurant. She is a known hypertensive on atenolol 50 mg daily and BP is well controlled. She is also on amlodipine 5 mg daily. Two doses of IM adrenaline has been given without improvement.
Which medication may prove helpful in this patient?
Your Answer:
Correct Answer: IM Glucagon
Explanation:Resistant to the effects of adrenaline in anaphylaxis is seen in patients taking beta-blockers.
Glucagon can be used to overcome the effects of the beta-blockade if initial doses of adrenaline are unsuccessful in patients taking beta-blockers.
-
This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
-
-
Question 36
Incorrect
-
A patient is sent in to ED by her GP with hyponatraemia and hyperkalaemia. There is most likely to be a deficiency in which of the following hormones:
Your Answer:
Correct Answer: Aldosterone
Explanation:A deficiency of aldosterone, as seen in adrenal insufficiency, can result in hyponatraemia and hyperkalaemia.
-
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 37
Incorrect
-
Which of the following is not true regarding the structure and function of glomerular filtration membrane?
Your Answer:
Correct Answer: The absence of a basement membrane reduces impedance to filtration
Explanation:The glomerular filtration membrane is composed of fenestrated capillary endothelium, basement membrane, and filtration slits. It is an organized, semipermeable membrane preventing the passage of most of the proteins into the urine.
The anatomical arrangement of the glomerular filtration membrane maximizes the surface area available for filtration. The arrangement of its arterioles results in high hydrostatic pressures and facilitates filtration.
Fenestrated capillary endothelium of the glomerular filtration membrane is with relatively large pores. It allows the free movement of plasma proteins and solutes but still restricts the movement of blood cells.
Filtration slits are the smallest filters and restrict the movement of plasma proteins but still allow free movement of ions and nutrients.
The glomerular basement membrane (GBM) is a critical component of the glomerular filtration membrane. Thus, it is not true that its absence will reduce the resistance of flow. The basement membrane is true to be more selective and contains negatively charged glycoproteins. However, it still allows free passage of water, nutrients, and ions. Severe structural abnormalities of the GBM can result in protein (albumin) leakage.
-
This question is part of the following fields:
- Physiology
- Renal Physiology
-
-
Question 38
Incorrect
-
Which of these organisms is commonly spread by droplet transmission?
Your Answer:
Correct Answer: Neisseria meningitidis
Explanation:Droplets are airborne particles greater than 5 µm in size. Droplet transmission occurs during talking, coughing and sneezing where respiratory droplets are generated.
Examples of organisms transmitted by the droplet route include:
Neisseria meningitidis
Respiratory syncytial virus
Parainfluenza virus
Bordetella pertussis
Influenza virusPoliovirus and Rotavirus are transmitted by the faeco-oral route
Hepatitis B is transmitted by Sexual route
Staphylococcus aureus is transmitted by direct contact
-
This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
-
-
Question 39
Incorrect
-
A 12-year-old boy presents to you with a history of fever. A rash began as small red dots on the face, scalp, torso, upper arms and legs shortly afterwards and has now progressed to small blisters and pustules. You make a diagnosis of chickenpox.
The following complications of chickenpox is the LEAST likely.
Your Answer:
Correct Answer: Bronchospasm
Explanation:Chickenpox (varicella zoster) is a highly contagious airborne disease and has an incubation period of between 7-21 days. It often has a prodromal phase when there is a fever, aches and headaches, dry cough, and sore throat before onset of rash.
Some recognized complications of chickenpox are:
Orchitis
Hepatitis
Pneumonia
Encephalitis
Infected spots
Otitis media
Myocarditis
Glomerulonephritis
Appendicitis
Pancreatitis -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 40
Incorrect
-
A young female was diagnosed with a urinary tract infection and was sent home with medications. However, after 48 hours of discharge, she returned to the hospital because there had been no relief from her symptoms. She is pregnant in her second trimester.
The urine sensitivity test report is still unavailable. Fresh blood tests were sent, and her estimated GFR is calculated to be >60 ml/minute.
She was prescribed nitrofurantoin 100 mg modified-release orally twice a day for two days.
Out of the following, which antibiotic is most appropriate to be prescribed to this patient?Your Answer:
Correct Answer: Cefalexin
Explanation:The NICE guidelines for pregnant women with lower UTIs are:
1. Prescribe an antibiotic immediately, taking into account the previous urine culture and susceptibility results or avoiding past antibiotics that may have caused resistance
2. Obtain a midstream urine sample before starting antibiotics and send for urine culture and susceptibility
– Review the choice of antibiotic when the results are available
– change the antibiotic according to susceptibility results if the bacteria are resistant, using a narrow-spectrum antibiotic wherever possibleThe first choice of antibiotics for pregnant women aged 12 years and over is:
1. Nitrofurantoin
100 mg modified-release PO BD for 3 days – if eGFR >45 ml/minuteThe second-choice (no improvement in lower UTI symptoms on first-choice for at least 48 hours, or when first-choice is not suitable) are:
1. Amoxicillin
500 mg PO TDS for seven days (ONLY if culture results available and susceptible)
2. Cefalexin
500 mg BD for seven days
Alternative second-choices – consult local microbiologist, choose antibiotics based on culture and sensitivity results -
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 41
Incorrect
-
Regarding fibrinolytics, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: Fibrinolytic drugs act as thrombolytics by directly degrading the fibrin mesh and so breaking up thrombi.
Explanation:Fibrinolytic drugs act as thrombolytics by activating plasminogen to form plasmin, which degrades fibrin and so breaks up thrombi.
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 42
Incorrect
-
A lesion to which part of the optic radiation will result in contralateral homonymous inferior quadrantanopia?
Your Answer:
Correct Answer: Right parietal lobe
Explanation:A visual loss in the lower left quadrant in both visual fields is an indication of an inferior homonymous. This is due to a lesion of the superior fibres of the optic radiation in the parietal lobe on the contralateral side of the visual pathway.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 43
Incorrect
-
In a ward round, you come across a patient's treatment chart prescribed an antibiotic to fight his infection. This antibiotic is a protein synthesis inhibitor.
Which of the following antimicrobial drugs is prescribed to this patient?Your Answer:
Correct 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 preventing initiation of protein synthesis.
Vancomycin inhibits cell wall peptidoglycan formation by binding the D-Ala-D-Ala portion of cell wall precursors.
Penicillins and cephalosporins are the major antibiotics that inhibit bacterial cell wall synthesis. They inactivate transpeptidases that help cross-link peptidoglycans in cell walls.
Metronidazole and the other 5-nitroimidazole agents inhibit nucleic acid synthesis by forming toxic free radical metabolites in the bacterial cell that damage DNA.
Ciprofloxacin inhibits prokaryotic enzymes topoisomerase II (DNA gyrase) and topoisomerase IV.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 44
Incorrect
-
The most important nerve for plantar flexion of the foot at the ankle joint is:
Your Answer:
Correct Answer: Tibial nerve
Explanation:Muscles of the posterior compartment of the leg, innervated by the tibial nerve, perform plantar flexion of the foot at the ankle joint. The fibularis longus (innervated by the superficial fibular nerve) assists in plantar flexion but is not the most important.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 45
Incorrect
-
Identify the type of graph described below:
This graph has been used to create visual representations to communicate the risks and benefits of treatments using 4 face categories.Your Answer:
Correct Answer: Cates plot
Explanation:Cates Plot, since 1999, has been used to create visual representations to communicate the risks and benefits of treatments. The essence of Cates Plot is the use of 4 face categories to visually indicate the following:
People not affected by a treatment (green faces for those with a good outcome and red for those with a bad outcome)
People for which treatment changes their category from a bad outcome to a good outcome (yellow faces)
People for which treatment causes an adverse event and changes their category from a good outcome to a bad outcome (crossed out green faces) -
This question is part of the following fields:
- Evidence Based Medicine
-
-
Question 46
Incorrect
-
Which of the following is NOT a typical electrolyte disturbance caused by furosemide:
Your Answer:
Correct Answer: Hypercalcaemia
Explanation:Adverse effects of loop diuretics include:
Mild gastrointestinal disturbances, pancreatitis and hepatic encephalopathy
Hyperglycaemia
Acute urinary retention
Water and electrolyte imbalance
Hyponatraemia, hypocalcaemia, hypokalaemia, hypomagnesaemia, hypochloraemiaHypotension, hypovolaemia, dehydration, and venous thromboembolism
Metabolic alkalosis
Hyperuricaemia
Blood disorders (bone marrow suppression, thrombocytopenia, and leucopenia)
Visual disturbance, tinnitus and deafness
Hypersensitivity reactions -
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 47
Incorrect
-
The most common site of ectopic pregnancy is?
Your Answer:
Correct Answer: Ampulla of Fallopian tube
Explanation:Nearly 95% of ectopic pregnancies are implanted in the various segments of the fallopian tube and give rise to fimbrial, ampullary, isthmic, or interstitial tubal pregnancies. The ampulla is the most frequent site, followed by the isthmus. The remaining 5% of non tubal ectopic pregnancies implant in the ovary, peritoneal cavity, cervix, or prior caesarean scar.
-
This question is part of the following fields:
- Abdomen And Pelvis
- Anatomy
-
-
Question 48
Incorrect
-
A 56-year-old man presents with pneumonia 8 days after being admitted for an open fracture of his tibia and fibula. Upon history taking and observation, it was established that he has no known drug allergies, has coarse left basal crackles and evidence of consolidation in the left lower lobe based on his chest X-ray.
Which of the following antibacterial agents would be the most appropriate to prescribe according to the latest NICE guidelines?Your Answer:
Correct Answer: Ciprofloxacin
Explanation:The current NICE guidelines for hospital-acquired pneumonia are as follow:
– First-choice oral antibiotic if non‑severe symptoms or signs, and not at higher risk of resistance (guided by microbiological results when available): co-amoxiclav– Alternative oral antibiotics if non‑severe symptoms or signs, and not at higher risk of resistance, for penicillin allergy or if co‑amoxiclav unsuitable (based on specialist microbiological advice and local resistance data): doxycycline, cefalexin, co-trimoxazole, levofloxacin
– First-choice intravenous antibiotics if severe symptoms or signs (for example, symptoms or signs of sepsis) or at higher risk of resistance (based on specialist microbiological advice and local resistance data): piperacillin with tazobactam, ceftazidime, ceftriaxone, cefuroxime, meropenem, ceftazidime with avibactam, levofloxacin
– Antibiotics to be added if suspected or confirmed methicillin-resistant Staphylococcus aureus infection (dual therapy with a first-choice intravenous antibiotic): vancomycin, teicoplanin, linezolid
-
This question is part of the following fields:
- Microbiology
- Principles Of Microbiology
-
-
Question 49
Incorrect
-
A 7-year-old boy is brought to the emergency room with complaints of a red and painful left eye. Upon physical examination, it was noted that there is the presence of conjunctival erythema. A mucopurulent discharge and crusting of the lid was also evident. A diagnosis of bacterial conjunctivitis was made.
According to the latest NICE guidelines, which of the following should NOT be a part of the management of this patient?Your Answer:
Correct Answer: Topical antibiotics should be prescribed routinely
Explanation:The following are the NICE guidelines on the management of bacterial conjunctivitis:
– Infective conjunctivitis is a self-limiting illness that usually settles without treatment within 1-2 weeks. If symptoms persist for longer than two weeks they should return for review.
– Seek medical attention urgently if marked eye pain or photophobia, loss of visual acuity, or marked redness of the eye develop.
– Remove contact lenses, if worn, until all symptoms and signs of infection have completely resolved and any treatment has been completed for 24 hours.
– Lubricant eye drops may reduce eye discomfort; these are available over the counter, as well as on prescription.
– Clean away infected secretions from eyelids and lashes with cotton wool soaked in water.
– Wash hands regularly, particularly after touching the eyes.
– Avoid sharing pillows and towels.
– It is not necessary to exclude a child from school or childcare if they have infective conjunctivitis, as mild infectious illnesses should not interrupt school attendance. An exception would be if there is an outbreak of infective conjunctivitis, when advice should be sought from the Health Protection Agency by the school.
– Adults who work in close contact with others, or with vulnerable patients, should avoid such contact until the discharge has settled. -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 50
Incorrect
-
You've been summoned to a young man in the resus area who has an SVT. You decide to use adenosine after trying several vagal manoeuvres without success.
The use of adenosine is not contraindicated in which of the following situations?Your Answer:
Correct Answer: Concurrent use of a beta-blocker
Explanation:The use of a beta-blocker at the same time increases the risk of myocardial depression, but it is not a contraindication.
The use of adenosine is contraindicated in the following situations:
Asthma
COPD (chronic obstructive pulmonary disease)
Decompensated heart failure
Long QT syndrome
AV block in the second or third degree
Sinusitis is a condition in which the sinuses become (unless pacemaker fitted)
Hypotension that is severe -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 51
Incorrect
-
What is the primary function of the mitochondria?
Your Answer:
Correct Answer: The production of the cell's supply of chemical energy
Explanation:The mitochondria is responsible for the production of the cell’s supply of chemical energy. It does this by using molecular oxygen, sugar and small fatty acid molecules to generate adenosine triphosphate (ATP) by a process ss known as oxidative phosphorylation. An enzyme called ATP synthase is required.
Transcription of ribosomal RNA occurs in the nucleolus
Production of messenger RNA occur in the nucleus
Production of lysosome occurs in the Golgi apparatus
The post-translational processing of newly made proteins occurs in the endoplasmic reticulum
-
This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
-
-
Question 52
Incorrect
-
An 11-year-old girl presents with a 5-day history of persistent fever despite regular paracetamol, throbbing left ear pain, ear discharge and deafness. Her parents have observed that she is not her usual self, not eating well, and has been lethargic. On examination there is a tender swelling in the post auricular region on the left hand side.
What is the most likely causative organism?
Your Answer:
Correct Answer: Streptococcus pneumonia
Explanation:Acute mastoiditis is a complication (rare) of acute otitis media (AOM) and the commonest causative organism is Streptococcus pneumoniae.
Generally, acute mastoiditis presents with:
Pyrexia
Recent history of AOM
Mastoid swelling and erythema
Otalgia
Otorrhoea and perforation of tympanic membrane
Post-auricular pain
Protrusion of the ears -
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 53
Incorrect
-
Which of the following medications may lessen warfarin's anticoagulant effect:
Your Answer:
Correct Answer: Phenytoin
Explanation:Phenytoin will decrease the level or effect of warfarin by affecting hepatic/intestinal enzyme CYP3A4 metabolism.
Metronidazole will increase the level or effect of warfarin by affecting hepatic enzyme CYP2C9/10 metabolism.
NSAIDs, when given with Warfarin, increase anticoagulation. -
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 54
Incorrect
-
A 25-year-old female arrives at the emergency room with a severe case of asthma. When she doesn't seem to be improving after initial treatment, you decide to start an aminophylline infusion.
From the options below, which is Aminophylline's main mechanism of action?Your Answer:
Correct Answer: Phosphodiesterase inhibition
Explanation:Theophylline and Ethylenediamine are combined in a 2:1 ratio to form Aminophylline. Its solubility is improved by the addition of Ethylenediamine. It has a lower potency and a shorter duration of action than Theophylline.
It is used to treat the following conditions:
Heart failure
It is used to treat the following conditions:
COPD
BradycardiasAminophylline has the following properties:
Phosphodiesterase inhibitor that increases intracellular cAMP and relaxes smooth muscle in the bronchial airways and pulmonary blood vessels.
Mast cell stabilization is achieved by using a non-selective adenosine receptor antagonist.
It has slight positive inotropic and chronotropic effects, increasing cardiac output and decreasing systemic vascular resistance, lowering arterial blood pressure. It has been used historically in the treatment of refractory heart failure and is indicated by the current ALS guidelines as a substitute treatment for bradycardia.The daily oral dose for adults is 900 mg, divided into 2-3 doses. For severe asthma or COPD, a loading dosage of 5 mg/kg over 10-20 minutes is given, followed by a continuous infusion of 0.5 mg/kg/hour. The therapeutic range is small (10-20 microgram/ml), hence assessments of aminophylline plasma concentrations are useful during long-term treatment.
-
This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
-
-
Question 55
Incorrect
-
Cardiac myocytes are connected to each other by which of the following:
Your Answer:
Correct Answer: Intercalated discs
Explanation:Adjacent cardiac myocytes are connected to each other by intercalated discs. The intercalated discs provide both a structural attachment by ‘glueing’ cells together at desmosomes and an electrical contact made up of proteins called connexons, called a gap junction, which essentially creates a low-resistance pathway between cells.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 56
Incorrect
-
Regarding likelihood ratios, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: Likelihood ratios, like predictive values, are affected by the prevalence of the disease in the population.
Explanation:A likelihood ratio is a measure of the diagnostic value of a test. Likelihood ratios show how many times more likely patients with a disease are to have a particular test result than patients without the disease. Likelihood ratios are more useful than predictive values because they are calculated from sensitivity and specificity and therefore remain constant even when the prevalence of the disorder changes.
-
This question is part of the following fields:
- Evidence Based Medicine
- Statistics
-
-
Question 57
Incorrect
-
Alpha cells of the endocrine pancreas produce which of the following hormones:
Your Answer:
Correct Answer: Glucagon
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.
-
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 58
Incorrect
-
Regarding chemical control of respiration, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: The blood-brain barrier is freely permeable to HCO3 - ions.
Explanation:CSF is separated from the blood by the blood-brain barrier. This barrier is impermeable to polar molecules such as H+and HCO3-but CO2can diffuse across it easily. The pH of CSF is therefore determined by the arterial PCO2and the CSF HCO3-and is not affected by blood pH.
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 59
Incorrect
-
A patient with diplopia is found to have eye deviation downwards and outwards. The likely nerves that are affected are:
Your Answer:
Correct Answer: Oculomotor nerve
Explanation:The results of an oculomotor (CN III) nerve palsy are a depressed and abducted (down and out) eye, ptosis, diplopia, and a fixed and dilated pupil.
-
This question is part of the following fields:
- Anatomy
- Cranial Nerve Lesions
-
-
Question 60
Incorrect
-
Regarding the lumbar plexus, which of the following is a direct muscular branch?
Your Answer:
Correct Answer: Nerve to quadratus lumborum
Explanation:The lumbar plexus gives rise to several branches which supply various muscles and regions of the posterior abdominal wall and lower limb. These branches include the Iliohypogastric, ilioinguinal, genitofemoral, lateral femoral cutaneous, femoral and obturator nerves.
In addition, the lumbar plexus gives off muscular branches from its roots, a branch to the lumbosacral trunk and occasionally an accessory obturator nerve.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 61
Incorrect
-
Which of the following is required for vitamin B12 absorption:
Your Answer:
Correct Answer: Intrinsic factor
Explanation:Intrinsic factor is essential for the absorption of the small amounts of vitamin B12 normally present in the diet from the terminal ileum. The parietal cells of the stomach produce intrinsic factor, and following a gastrectomy, the absorption of vitamin B12 will be markedly reduced, and a deficiency state will exist.
-
This question is part of the following fields:
- Gastrointestinal
- Physiology
-
-
Question 62
Incorrect
-
An analytical cohort study aimed to determine a relationship between intake of dietary calcium and incidence of hip fractures among post-menopausal women. The following are the data obtained from the study:
No. of post-menopausal women who took Calcium: 500
No. of post-menopausal women who took Calcium and suffered a hip fracture: 10
No. of post-menopausal women who took placebo: 500
No. of post-menopausal women who took placebo and suffered a hip fracture: 25
Compute for the risk ratio of a hip fracture.Your Answer:
Correct Answer: 0.4
Explanation:Relative risk (RR) is a ratio of the probability of an event occurring in the exposed group versus the probability of the event occurring in the non-exposed group.
RR can be computed as the absolute risk of events in the treatment group (ART), divided by the absolute risk of events in the control group (ARC).
RR = ART/ARC
RR = (10/500) / (25/500)
RR = 0.4Recall that:
If RR < 1, then the intervention reduces the risk of the outcome.
If RR = 1, then the treatment has no effect on the outcome.
If RR > 1, then the intervention increases the risk of the outcome. -
This question is part of the following fields:
- Evidence Based Medicine
-
-
Question 63
Incorrect
-
The juxtacapillary receptors, or J receptors, are sensory cells that play an important role in the control of respiration.
At which of the following anatomical sites are the J receptors located? Select ONE answer only.Your Answer:
Correct Answer: The alveolar walls
Explanation:Juxtacapillary receptors (J receptors) are sensory cells that are located within the alveolar walls in juxtaposition to the pulmonary capillaries of the lung.
The J receptors are innervated by the vagus nerve and are activated by physical engorgement of the pulmonary capillaries or increased pulmonary interstitial volume, for example, in the presence of pulmonary oedema, pulmonary embolus, pneumonia and barotraumas. They may also be stimulated by hyperinflation of the lung.
Stimulation of the J receptors causes a reflex increase in breathing rate and is also thought to be involved in the sensation of dyspnoea. The reflex response that is produced is apnoea, followed by rapid breathing, bradycardia, and hypotension. -
This question is part of the following fields:
- Physiology
- Respiratory Physiology
-
-
Question 64
Incorrect
-
A 28 year old man presents with abdominal pain and constipation, and bloods show hypocalcaemia. Which of the following hormones is increased as a result of hypocalcaemia?
Your Answer:
Correct Answer: Parathyroid hormone
Explanation:Parathyroid hormone (PTH), also called parathormone or parathyrin, is a peptide hormone that is secreted by the parathyroid glands, which lie immediately behind the thyroid gland. In particular, this hormone is made by chief cells. It regulates the serum calcium concentration through its effects on bone, kidney, and intestine. This hormone is primarily released in response to decreasing plasma Ca2+ concentration and it serves to increase plasma calcium levels and decrease plasma phosphate levels.
PTH activates Ca2+entry channels in the apical membrane and the Ca2+ATPase pump in the basolateral membrane and as a result, increases calcium reabsorption in the distal tubule of the nephron. It inhibits reabsorption of phosphate and this increases its excretion by in the proximal tubule of the nephron. -
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 65
Incorrect
-
You're examining a 58-year-old male who has cellulitis in his left leg. Because he is allergic to penicillin, you start him on erythromycin.
Which of the following statements about erythromycin is correct?Your Answer:
Correct Answer: It can be used to treat Legionnaire’s disease
Explanation:Bacteriostatic antibiotics include erythromycin and other macrolide antibiotics. They work by attaching to the bacterial ribosome’s 50S subunit, preventing translocation and thereby protein synthesis. Macrolide antibiotics are actively concentrated inside leukocytes and delivered to the infection site as a result.
Erythromycin is an orally active antibiotic that can also be given intravenously. It is metabolized in the liver and eliminated in the bile and has a biological half-life of 1.5 hours.
It has a similar antibacterial spectrum to benzylpenicillin (i.e., a narrow spectrum, primarily against Gram-positive pathogens) and can be used as a penicillin substitute in people who are allergic to penicillin.
Erythromycin is unsuccessful in the treatment of meningitis because it does not penetrate the central nervous system well enough. It is efficient against a variety of unusual pathogens, unlike penicillin. -
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 66
Incorrect
-
You examine a patient's blood tests and discover that her electrolyte levels are abnormal.
Which of the following is the major extracellular cation?Your Answer:
Correct Answer: Sodium
Explanation:Electrolytes are compounds that may conduct an electrical current and dissociate in solution. Extracellular and intracellular fluids contain these chemicals. The predominant cation in extracellular fluid is sodium, whereas the major anion is chloride. Potassium is the most abundant cation in the intracellular fluid, while phosphate is the most abundant anion. These electrolytes are necessary for homeostasis to be maintained.
-
This question is part of the following fields:
- Basic Cellular Physiology
- Physiology
-
-
Question 67
Incorrect
-
A patient presents with a rash for a dermatological examination. A flat circumscribed area of discoloured skin measuring 0.7 cm in diameter is seen on examination.
What is the best description of this rash that you have found on examination?
Your Answer:
Correct Answer: Macule
Explanation:A macule is a flat, well circumscribed area of discoloured skin less than 1 cm in diameter with no changes in the thickness or texture of the skin.
A vesicle is a visible collection of clear fluid measuring less than 0.5 cm in diameter.
A papule is a solid, well circumscribed, skin elevation measuring less than 0.5 cm in diameter.
A nodule is a solid, well circumscribed, raised area that lies in or under the skin and measures greater than 0.5 cm in diameter. They are usually painless.
A plaque is a palpable skin lesion that is elevated and measures >1cm in diameter.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 68
Incorrect
-
The pathophysiology of Addison's disease is as follows:
Your Answer:
Correct Answer: Adrenocortical insufficiency
Explanation:Primary adrenal insufficiency, also known as Addison’s disease, occurs when the adrenal glands cannot produce an adequate amount of hormones despite a normal or increased corticotropin (ACTH) level.
-
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 69
Incorrect
-
You are planning on starting antibiotic therapy for a patient with a diagnosis of gonorrhoea.
Which of these is the MOST appropriate antibiotic combination?Your Answer:
Correct Answer: Ceftriaxone and azithromycin
Explanation:Currently, ceftriaxone in combination with azithromycin or doxycycline is the combination of antibiotics used in the treatment of gonorrhoea.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 70
Incorrect
-
Regarding cross-sectional studies, which of the following statements is CORRECT:
Your Answer:
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.
-
This question is part of the following fields:
- Evidence Based Medicine
- Study Methodology
-
-
Question 71
Incorrect
-
A 39-year-old man with a long history of depression presents after intentionally overdoing his heart medication. Verapamil immediate-release 240 mg is the tablet he takes for this condition, he says. He took the pills about 30 minutes ago, but his wife discovered him right away and rushed him to the emergency room.
Which of the following is a verapamil toxicity?Your Answer:
Correct Answer: Negative inotropy
Explanation:Overdosing on calcium-channel blockers should always be taken seriously and regarded as potentially fatal. Verapamil and diltiazem are the two most lethal calcium-channel blockers in overdose. These work by binding the alpha-1 subunit of L-type calcium channels, preventing calcium from entering the cell. In cardiac myocytes, vascular smooth muscle cells, and islet beta-cells, these channels play an important role.
The following summarises the toxicity of calcium-channel blockers:
Cardiac effects
Vascular smooth muscle tone affects
Metabolic effects
Excessive negative inotropy: myocardial depression
Negative chronotropy: sinus bradycardia
Negative dromotropy: atrioventricular node blockade
Decreased afterload
Systemic hypotension
Coronary vasodilation
Hypoinsulinaemia
Calcium channel blocker-induced insulin resistance -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 72
Incorrect
-
A 70-year-old patient presents with a chronic digoxin overdose. She has vomited several times, is extremely tired, and her vision 'appears yellow,' according to her.
Which of the following is a reason for this patient's use of Digifab?Your Answer:
Correct Answer: Coexistent renal failure
Explanation:An antidote for digoxin overdose is digoxin-specific antibody (Digifab). It’s a lyophilized preparation of digoxin-immune ovine Fab immunoglobulin fragments that’s sterile, purified, and lyophilized. These fragments were extracted from the blood of healthy sheep that had been immunised with a digoxin derivative called digoxin-dicarboxymethoxylamine (DDMA), a digoxin analogue that contains the functionally important cyclopentaperhydrophenanthrene:lactone ring moiety coupled to keyhole limpet hemocyanin (KLH).
Digifab has a higher affinity for digoxin than digoxin does for its sodium pump receptor, which is thought to be the site of its therapeutic and toxic effects. When given to a patient who is intoxicated, Digifab binds to digoxin molecules, lowering free digoxin levels and shifting the equilibrium away from binding to receptors, reducing cardio-toxic effects. The kidney and reticuloendothelial system then clear the Fab-digoxin complexes.
The following summarises the indications for Digifab in acute and chronic digoxin toxicity:
Acute digoxin toxicity
Chronic digoxin toxicity
Cardiac arrest
Life-threatening arrhythmia
Potassium level > 5 mmol/l
>10 mg digoxin ingested (adult)
>4 mg digoxin ingested (child)
Digoxin level > 12 ng/ml
Cardiac arrest
Life-threatening arrhythmia
Significant gastrointestinal symptoms
Symptoms of digoxin toxicity -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 73
Incorrect
-
In which of the following would you NOT typically see a neutropaenia:
Your Answer:
Correct Answer: Asplenism
Explanation:Causes of neutropaenia:
Drug-induced (e.g. chemotherapy, chloramphenicol, co-trimoxazole, phenytoin, carbamazepine, carbimazole, furosemide, chloroquine, clozapine, some DMARDs)
Benign (racial or familial)
Cyclical
Immune (e.g. SLE, Felty’s syndrome, hypersensitivity and anaphylaxis)
Leukaemia
Infections (e.g. HIV, hepatitis, fulminant bacterial infection)
General Pancytopaenia
Hypersplenism, aplastic anaemia, malignant infiltration of bone marrow, megaloblastic anaemia, chemotherapy, myelodysplasia -
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 74
Incorrect
-
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:
Correct 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.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 75
Incorrect
-
Which of the following is NOT a typical clinical feature of hypoglycaemia:
Your Answer:
Correct Answer: Polyuria
Explanation:Clinical features of hypoglycaemia:
Autonomic symptoms: Sweating, feeling hot, anxiety/agitation, palpitations, shaking, paraesthesia, dizziness
Neuroglycopaenic symptoms: Weakness, blurred vision, difficulty speaking, poor concentration, poor coordination, drowsiness, confusion, seizures, coma
Other symptoms: Nausea, fatigue, hunger -
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 76
Incorrect
-
A patient who shows symptoms of infection and is admitted under supervision of the medical team. The organism which caused this, is a Gram-negative bacterium, according to the culture. A penicillin therapy is suggested by the microbiologist.
Which of the penicillins listed below is the most effective against Gram-negative bacteria?Your Answer:
Correct Answer: Amoxicillin
Explanation:Amoxicillin and Ampicillin are more hydrophilic (broad-spectrum) penicillins than benzylpenicillin and phenoxymethylpenicillin. Because they may penetrate through gaps in the outer phospholipid membrane, they are effective against Gram-negative bacteria. Amoxicillin and Ampicillin are resistant to penicillinase-producing microbes.
Community-acquired pneumonia, otitis media, sinusitis, oral infections, and urinary tract infections are among the most prevalent conditions for which they are prescribed. The normal adult oral dose of Amoxicillin is 500 mg three times/day, which can be increased to 1 g three times/day if necessary. Ampicillin is given to adults in doses of 0.5-1 g every 6 hours.
-
This question is part of the following fields:
- Infections
- Pharmacology
-
-
Question 77
Incorrect
-
Chronic myeloid leukaemia is most common in middle-aged and elderly people. It is responsible for 20% of all leukemias.
Which of the following statements about CML is NOT TRUE?Your Answer:
Correct Answer: Serum B12 is typically low
Explanation:Chronic myeloid leukaemia is most common in middle-aged and elderly people. It is responsible for 20% of all leukemias. The majority of CML patients experience fatigue, weight loss, and excessive sweating.
The Philadelphia chromosome is found in over 90% of CML cases. A balanced translocation between chromosomes 9 and 22 is known as the Philadelphia chromosome.
Because white cells produce a B12 binding protein, serum B12 levels in CML are typically high.
In CML, the neutrophil alkaline phosphatase score is usually low.
Almost all patients with CML eventually progress to blast crisis, though this can take up to ten years. If any of the following features are present in a CML patient, a blast crisis is diagnosed:
In the blood or bone marrow, there are more than 20% myeloblasts or lymphoblasts.
On a bone marrow biopsy, large clusters of blasts were discovered.CML can be treated with tyrosine kinase inhibitors like imatinib and dasatinib if a chloroma (a solid tumour made up of myeloblasts that grows outside of the bone marrow) is present.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 78
Incorrect
-
The most important Complement protein for antigen opsonization is:
Your Answer:
Correct Answer: C3b
Explanation:Phagocytosis is largely responsible for depletion of cells coated with antibodies. Cells opsonized by IgG antibodies are recognized by phagocyte Fc receptors, which are specific for the Fc portions of some IgG subclasses. In addition, when IgM or IgG antibodies are deposited on the surfaces of cells, they may activate the complement system by the classical pathway. Complement activation generates by-products, mainly C3b and C4b, which are deposited on the surfaces of the cells and recognized by phagocytes that express receptors for these proteins. The net result is phagocytosis of the opsonized cells and their destruction.
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 79
Incorrect
-
A patient with pronounced tremor, muscle contractions, muscle spasms, and slowness of movement is brought in by his family. He has a long history of mental health issues for which he is currently treated with a variety of medications.
Which of the medications listed below is most likely to be the cause of these side effects?Your Answer:
Correct Answer: Haloperidol
Explanation:Acute dyskinesias and dystonic reactions, tardive dyskinesia (rhythmic, involuntary movements of the tongue, face, and jaw), Parkinsonism (tremor, bradykinesia, and rigidity), akinesia, akathisia, and neuroleptic malignant syndrome are all examples of extrapyramidal side effects. They are caused by dopamine depletion or blockade in the basal ganglia; this lack of dopamine frequently mimics idiopathic extrapyramidal pathologies.
The first-generation antipsychotics, which are strong dopamine D2 receptor antagonists, are the drugs most commonly associated with extrapyramidal side effects. Haloperidol and fluphenazine are the two drugs in this class that are most commonly associated with extrapyramidal side effects. Extrapyramidal adverse effects are less common in second-generation antipsychotics (e.g., olanzapine) than in first-generation antipsychotics.
Other drugs are linked to extrapyramidal symptoms as well, but at a lower rate. Some antidepressants, lithium, various anticonvulsants, antiemetics, and, in rare cases, oral contraceptive agents are among them.
-
This question is part of the following fields:
- CNS Pharmacology
- Pharmacology
-
-
Question 80
Incorrect
-
A 18 year old university student develops facial swelling and dark frothy urine. Urine dipstick demonstrates haematuria and proteinuria. Approximately 3 weeks ago, he was treated with oral antibiotics for a sore throat. His condition is most likely to be secondary to infection with:
Your Answer:
Correct Answer: Streptococcus pyogenes
Explanation:Post-streptococcal glomerulonephritis is a postinfectious immune-mediated reaction secondary to infection with Streptococcus pyogenes. It typically occurs 2 weeks or more after acute/initial infection, and presents with haematuria, reduced urine output, peripheral oedema, proteinuria, and hypertension. Permanent kidney damage is rare.
-
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 81
Incorrect
-
Question 82
Incorrect
-
Which of the following microbes is spread by a vector:
Your Answer:
Correct Answer: Plasmodium falciparum
Explanation:The female Anopheles mosquito is the vector for Plasmodium falciparum transmission. Treponema pallidum is transmitted through sexual transmission or direct skin contact. Clostridium perfringens is spread by direct skin contact or through oral-faecal route. The oral-faecal pathway is how Vibrio cholerae spreads. Mycoplasma tuberculosis is spread via the airborne route.
-
This question is part of the following fields:
- Microbiology
- Principles
-
-
Question 83
Incorrect
-
Which of the following clinical features would you NOT expect to see in a tibial nerve palsy:
Your Answer:
Correct Answer: Weakened eversion of the foot
Explanation:Damage to the tibial nerve results in loss of plantarflexion of the ankle and weakness of inversion of the foot resulting in a shuffling gait, clawing of the toes and loss of sensation in its cutaneous distribution.
-
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 84
Incorrect
-
Which of the following terms describes the proportion of individuals with a negative test result who actually do not have a disease:
Your Answer:
Correct Answer: Negative predictive value
Explanation:Negative predictive value (NPV) is the proportion of individuals with a negative test result who do not have the disease.
NPV = d/(c+d) -
This question is part of the following fields:
- Evidence Based Medicine
- Statistics
-
-
Question 85
Incorrect
-
The ventilation over perfusion ratio is highest at the apex of the lung. What is the approximate V/Q ratio at this area?
Your Answer:
Correct Answer: 3.3
Explanation:The ventilation/perfusion ratio (V/Q ratio) is a ratio used to assess the efficiency and adequacy of the matching ventilation and perfusion. The ideal V/Q ratio is 1.
Any mismatch between ventilation and perfusion will be evident in the V/Q ratio. If perfusion is normal but ventilation is reduced, the V/Q ratio will be less than 1, whereas if ventilation is normal, but perfusion is reduced, the V/Q ratio will be greater than 1.
If the alveoli were ventilated but not perfused at all, then the V/Q ratio would be infinity. The V/Q ratio is also affected by location. The various areas of the lungs have a different V/Q ratio since ventilation and perfusion increase from the apex to the base of the lungs. The apex of the lungs has a V/Q ratio of approximately 3.3.
-
This question is part of the following fields:
- Physiology
- Respiratory Physiology
-
-
Question 86
Incorrect
-
A 55-year-old woman was complaining of headaches. On examination, the patient is found to have weakness on the left side of her body and her eyes are deviated towards the right hand side. These are signs of damage to which of the following areas?
Your Answer:
Correct Answer: Frontal lobe
Explanation:Some potential symptoms of frontal lobe damage can include loss of movement, either partial or complete, on the opposite side of the body.
In the patient’s case, it is a result of motor cortex damage on the right side since her left side of the body is affected. The conjugate eye deviation symptom towards the side of the lesion is a result of damage to the frontal eye field.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 87
Incorrect
-
A 30-year-old woman is transfused following a diagnosis of anaemia secondary to heavy vaginal bleeding. She complains of feeling hot and cold during transfusion of the second unit and her temperature is 38.5ºC. Prior to the transfusion, her temperature was 37ºC. She has no other symptoms.
Which of these transfusions reactions most likely occurred?Your Answer:
Correct Answer: Febrile transfusion reaction
Explanation:Febrile transfusion reactions presents with an unexpected temperature rise (≥ 38ºC or ≥ 1ºC above baseline, if baseline ≥ 37ºC) during or shortly after transfusion. It is usually an isolated finding and the fever is accompanied by chills and malaise occasionally.
Allergic reaction is commonly caused by foreign plasma proteins but may be due to anti-IgA. Allergic type reactions usually present with urticaria, pruritus, hives. Associations include laryngeal oedema or bronchospasm.
Acute haemolytic reaction aka immediate haemolytic transfusion reaction presents with fever, chills, pain at transfusion site, nausea, vomiting, dark urine and feeling of ‘impending doom’. Often, it occurs due to ABO incompatibility.
Transfusion-associated circulatory overload (TACO) presents as acute or worsening respiratory distress within 6 hours of transfusion of a large volume of blood. It is common in patients with diminished cardiac reserve or chronic anaemia. Elderly patients, infants and severely anaemic patients are particularly susceptible. Clinical features of TACO include: Acute respiratory distress, Tachycardia, Hypertension, Acute/worsening pulmonary oedema on chest X-ray. The BNP is usually raised to at least 1.5 times the pre-transfusion baseline.
Transfusion-related lung injury (TRALI) is a form of acute respiratory distress caused by the donor plasma containing antibodies against the patient’s leukocytes. It is defined as hypoxia and bilateral pulmonary oedema that occurs within 6 hours of a transfusion in the absence of other causes of acute lung injury. Clinical features include Breathlessness, cough, frothy sputum, hypertension or hypotension, hypoxia and fever. Chest X-ray shows multiple perihilar nodules with infiltration of the lower lung fields.
-
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 88
Incorrect
-
Atrial natriuretic peptide (ANP) is primarily produced in response to:
Your Answer:
Correct Answer: An increase in intravascular fluid volume
Explanation:Atrial natriuretic peptide (ANP) is released from cardiac atrial muscle cells in response to atrial stretch caused by an increase in intravascular fluid volume and is also produced in collecting duct cells.
Atrial natriuretic peptide acts to inhibit sodium reabsorption in the distal nephron. -
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 89
Incorrect
-
Regarding the resting membrane potential, which of the following statements is CORRECT:
Your Answer:
Correct Answer: The resting cell membrane is more permeable to K + ions than to Na + ions.
Explanation:A membrane potential is a property of all cell membranes, but the ability to generate an action potential is only a property of excitable tissues. The resting membrane is more permeable to K+and Cl-than to other ions (and relatively impermeable to Na+); therefore the resting membrane potential is primarily determined by the K+equilibrium potential. At rest the inside of the cell is negative relative to the outside. In most neurones the resting potential has a value of approximately -70 mV.
-
This question is part of the following fields:
- Basic Cellular
- Physiology
-
-
Question 90
Incorrect
-
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:
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.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 91
Incorrect
-
A 26-year-old man is involved in a motorcycle accident that results in an open fracture of his tibia and fibula. The nerve that innervates peroneus tertius is damaged as a consequence of his injuries.
Peroneus tertius receives its innervation from which of the following nerves? Select ONE answer only.Your Answer:
Correct Answer: Deep peroneal nerve
Explanation:Peroneus brevis is innervated by the superficial peroneal nerve.
Peroneus longus is innervated by the superficial peroneal nerve.
Peroneus tertius is innervated by the deep peroneal nerve. -
This question is part of the following fields:
- Anatomy
- Lower Limb
-
-
Question 92
Incorrect
-
The following statements are not true of the flexor digiti minimi brevis, except?
Your Answer:
Correct Answer: It is situated on the radial border of abductor digiti minimi
Explanation:Flexor digiti minimi brevis muscle is located on the ulnar side of the palm, lying on the radial border of the abductor digiti minimi. Together with the abductor digiti minimi and opponens digiti minimi muscles, it forms the hypothenar eminence. The muscle is situated inferior and lateral to adductor digiti minimi muscle and superior and medial to opponens digiti minimi muscle. The proximal parts of flexor digiti minimi brevis and abductor digiti minimi muscles form a gap through which deep branches of the ulnar artery and ulnar nerve pass.
-
This question is part of the following fields:
- Anatomy
- Upper Limb
-
-
Question 93
Incorrect
-
Where does angiotensin II directly act on the renal nephron:
Your Answer:
Correct Answer: Proximal tubule
Explanation:Angiotensin II acts to directly increase Na+reabsorption from the proximal tubule (by activating Na+/H+antiporters).
-
This question is part of the following fields:
- Physiology
- Renal
-
-
Question 94
Incorrect
-
What is the earliest physiological effect that causes postural hypotension:
Your Answer:
Correct Answer: A fall in central venous pressure
Explanation:When autonomic reflexes are impaired or intravascular volume is markedly depleted, a significant reduction in blood pressure occurs upon standing, a phenomenon termed Postural Hypotension (orthostatic hypotension). Orthostatic hypotension can cause dizziness, syncope, and even angina or stroke. When autonomic reflexes are impaired, blood pressure falls progressively after standing because the gravitational pooling of blood in the legs cannot be compensated by sympathetic vasoconstriction.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 95
Incorrect
-
A 68-year-old man with BPH presents to the emergency department in significant pain secondary to urinary retention. What is the location of the neuronal cell bodies that are responsible for urinary bladder discomfort sensation?
Your Answer:
Correct Answer: Dorsal root ganglia of spinal cord levels S2, S3 and S4
Explanation:The activation of stretch receptors with visceral afferents relayed through the pelvic nerve plexus and into the pelvic splanchnic nerves causes bladder pain. The sensory fibres of spinal nerves S2 – S4 enter the dorsal root ganglia.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 96
Incorrect
-
Which of the following is the most likely causative organism of acute epiglottitis in a 6 year old?
Your Answer:
Correct Answer: Streptococcus pneumoniae
Explanation:Since the introduction of the HIB vaccine, most cases of acute epiglottitis are now caused by Streptococcus spp. The condition is now rare in children.
-
This question is part of the following fields:
- Microbiology
- Specific Pathogen Groups
-
-
Question 97
Incorrect
-
A dermatological examination of a patient presenting with a lump shows a visible collection of fluid measuring 0.3 cm in diameter.
Which one of these best describes the lump you have found on examination?Your Answer:
Correct Answer: Vesicle
Explanation:A vesicle is a visible collection of fluid measuring less than 0.5 cm in diameter.
A furuncle, or boil, is a pyogenic infection of the hair follicle commonly caused by infection with Staphylococcus aureus.
A carbuncle is a collection of individual boils clustered together.
A bulla is a visible collection of clear fluid measuring greater than 0.5 cm in diameter.
A pustule is a small visible skin elevation containing an accumulation of pus.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 98
Incorrect
-
Question 99
Incorrect
-
A 54-year-old woman presents with polyuria and polydipsia. She is known to suffer from bipolar disorder, which has been well controlled by the use of lithium for many years.
What is the SINGLE most likely diagnosis?Your Answer:
Correct Answer: Nephrogenic diabetes insipidus
Explanation:Diabetes insipidus is the inability to produce concentrated urine. It is characterised by the presence of excessive thirst, polyuria and polydipsia. There are two distinct types of diabetes insipidus:
Cranial (central) diabetes insipidus and;
Nephrogenic diabetes insipidus
Cranial diabetes insipidus is caused by a deficiency of vasopressin (anti-diuretic hormone). Patients with cranial diabetes insipidus can have a urine output as high as 10-15 litres per 24 hours, but adequate fluid intake allows most patients to maintain normonatraemia. 30% of cases are idiopathic, and a further 30% are secondary to head injuries. Other causes include neurosurgery, brain tumours, meningitis, granulomatous disease (e.g. sarcoidosis) and drugs, such as naloxone and phenytoin. A very rare inherited form also exists that is associated with diabetes mellitus, optic atrophy, nerve deafness and bladder atonia.
Nephrogenic diabetes insipidus is caused by renal resistance to the action of vasopressin. As with cranial diabetes insipidus, urine output is markedly elevated. Serum sodium levels can be maintained by secondary polydipsia or can be elevated. Causes of nephrogenic diabetes insipidus include chronic renal disease, metabolic disorders (e.g. hypercalcaemia and hypokalaemia) and drugs, including long-term lithium usage and demeclocycline.
In view of the history of long-term lithium use, in this case, nephrogenic diabetes insipidus is the most likely diagnosis. -
This question is part of the following fields:
- Physiology
- Renal Physiology
-
-
Question 100
Incorrect
-
Renin is produced by which of the following:
Your Answer:
Correct Answer: Granular cells in the wall of the afferent arteriole
Explanation:Juxtaglomerular cells are specialised smooth muscle cells mainly in the walls of the afferent arterioles (and some in the efferent arterioles) which synthesise renin.
-
This question is part of the following fields:
- Physiology
- Renal
-
00
Correct
00
Incorrect
00
:
00
:
00
Session Time
00
:
00
Average Question Time (
Secs)