Paper 4 MCQs Flashcards
The following act by blocking cholinergic receptors:
a) trimetaphan
b) hexamethonium
c) ouabain
d) benzhexol
e) physostigmine
TTFTF
Esmolol:
a) has a negative inotropic effect
b) has no intrinsic sympathomimetic activity
c) causes a dose-dependent fall in heart rate
d) increases airways resistance
e) may prolong the duration of action of suxamethonium
TTTTT
Enflurane:
a) is a halogenated methyl-ethyl ether
b) has a blood/gas solubility coefficient of 1.43
c) lowers intracranial pressure
d) increases the tone of the pregnant uterus
e) causes a decrease in systemic vascular resistance
TFFFT
Morphine:
a) causes histamine release
b) has no active metabolites
c) undergoes extensive first-pass hepatic metabolism
d) has an elimination half-life of 3-4 hours
e) may be antagonised by pentazocine
TFTTT
Uterine tone is:
a) increased by ketamine
b) decreased by halothane
c) increased by beta-2 antagonists
d) unaffected by suxamethonium
e) decreased by nifedipine
TTTTF
Aspirin overdose causes:
a) thrombocytopenia
b) coma
c) metabolic acidosis
d) jaundice
e) pulmonary oedema
Non-depolarising neuromuscular blockers are potentiated by:
a) lithium
b) trimetaphan
c) diazepam
d) magnesium
e) suxamethonium
TFTTT
Atropine:
a) crosses the blood/brain barrier
b) can cause an initial bradycardia
c) increases the rate of gastric emptying
d) increases conduction through the A-V node
e) produces bronchoconstriction
TTFTF
Hepatotoxicity has been associated with:
a) diethyl ether
b) chloroform
c) cyclopropane
d) enflurane
e) halothane
FTFTT
The anticoagulant effect of warfarin:
a) is exerted directly on the blood
b) is slow in onset
c) can be reversed by vitamin K
d) is potentiated by phenylbutazone
e) is potentiated by barbiturates
FTTTF
The following may be used in the treatment of digoxin toxicity:
a) propranolol
b) lidocaine
c) phenytoin
d) calcium
e) potassium
TTTFT
Dobutamine:
a) is structurally similar to isoprenaline
b) activates adenyl cyclase
c) has a selective action on beta-1 adrenoreceptors
d) has a half-life of 2 minutes
e) increases the left ventricular end diastolic pressure
TTTTF
Organophosphorus anticholinesterases:
a) have an irreversible action
b) phosphorylate cholinesterase
c) produce more inhibition of acetyl cholinesterase than of plasma cholinesterase
d) can have their action reversed in the early stages by atropine
e) are readily absorbed through the skin
TTFTT
The following factors encourage passage of a substance across the cell membrane:
a) high lipid solubility
b) low concentration gradient
c) high molecular weight
d) negative hydrostatic pressure
e) high degree of ionisation
TFFFF
Amitriptyline in overdose causes:
a) cardiac arrhythmias
b) hypertension
c) restlessness
d) metabolic acidosis
e) jaundice
TFTTF
Low plasma cholinesterase activity:
a) is related to the patient’s blood group
b) has no effect on the action of decamethonium
c) occurs with organophosphorus poisoning
d) prolongs the action of esmolol
e) occurs in malnutrition
FFTFT
Sulphonylureas:
a) act by increasing insulin release
b) tend to produce weight loss
c) are suitable for use in pregnancy
d) are effective in correcting ketoacidosis
e) can produce hypoglycaemia
TFFFT
Side-effects of hydralazine include:
a) tachycardia
b) impotence
c) constipation
d) systemic lupus erythematosus
e) bronchoconstriction
TTFTF
The following are measures of scatter in statistical analysis:
a) mean
b) standard error of the mean
c) standard deviation
d) range
e) p of less than 0.5
FTTTF
Statistical tests are used to:
a) eliminate observer bias
b) eliminate placebo effect
c) show that results are true
d) show that the results did not occur by chance
e) show that the results are clinically significant
FFFTF
The liver:
a) receives most of its oxygen supply from the portal vein
b) has its highest oxygen tension at the centre of a lobule
c) produces heparin
d) has a normal portal venous pressure of greater than 20 mmHg
e) receives approximately 25% of the cardiac output
FFFFT
Skeletal muscle blood flow:
a) increases with norepinephrine
b) receives 50% of the cardiac output at rest
c) may cease during isometric contraction
d) increases with rhythmic contraction
e) increases with epinephrine
FFTTT
In thermoregulation:
a) respiratory heat loss is insignificant under normal conditions
b) brown fat is an important source of heat production in neonates
c) shivering is due to impulses conducted via autonomic efferents
d) peripheral vasoconstriction increases heat production
e) sweating is mediated by sympathetic adrenergic neurones
TTFFF
Epinephrine:
a) is synthesised by demethylation of norepinephrine
b) increases coronary blood flow
c) increases free fatty acids in the blood
d) mobilises glycogen stores from the liver
e) is metabolised in the plasma by monoamine oxidase
FTTTF
Glucagon:
a) is a positive inotrope
b) is produced by the B cells of the pancreas
c) stimulates production of free fatty acids in the blood
d) release is increased in starvation
e) stimulates glycogen synthesis
TFTTF
Surfactant:
a) is a mucopolypeptide
b) causes a decrease in surface tension
c) results in the same surface tension for different sized alveoli
d) causes an increase in compliance
e) production is reduced after a prolonged reduction in pulmonary blood flow
FTFFT
Sinus arrhythmia:
a) produces a lengthening of the P-R interval
b) produces a lengthening of the R-R interval
c) is maximal with breath holding
d) is more marked during exercise
e) is more marked in 70 year olds than in 20 year olds
FTFFF
A pressure-volume curve can be used for measuring:
a) the work of breathing
b) functional residual capacity
c) anatomical dead space
d) compliance
e) respiratory quotient
TFFTF
The absolute refractory period for cardiac muscle is:
a) as long as the entire action potential
b) the period when no further action potential can be stimulated
c) twice the length of the S-T interval
d) as long as the mechanical contraction
e) shorter for pacemaker tissue than for normal cardiac muscle
FTFFT
In a young normal adult:
a) the glomerular filtration rate is approximately 125 ml/min
b) the 24 hour urine creatinine content is approximately 800 mg
c) urine specific gravity is always less than 1000
d) renal blood flow is approximately 20% of cardiac output
e) over 50% of water reabsorption from the glomerular filtrate occurs in the collecting ducts
TFFTF
Total plasma calcium:
a) increases with phosphate
b) increases with a rise in albumin
c) changes its degree of ionisation with pH changes
d) is decreased in osteoporosis
e) is affected by vitamin D
FTTFT
There is increased intestinal motility with:
a) increased intraluminal pressure
b) anticholinesterase drugs
c) sympathetic block to T4
d) stimulation of the splanchnic nerves
e) increased circulating epinephrine
TTTFF
In a normal resting subject, a bradycardia would be expected following:
a) an increase in carotid sinus pressure
b) an increase in right atrial pressure
c) application of pressure to the eyeball
d) the release of a Valsalva manoevre
e) inspiration
TFTTF
The velocity of conduction of a nerve action potential:
a) is inversely related to the cross-sectional area of the axon
b) is faster in a myelinated fibre than in an unmyelinated one
c) is decreased by cooling the nerve
d) can exceed 100 m/s in humans
e) is highest in pre-ganglionic autonomic fibres
FTTTF
The placenta:
a) transports glucose from maternal to fetal blood by facilitated diffusion
b) can synthesise glycogen
c) actively transports oxygen from maternal to fetal blood
d) allows protein molecules to pass from maternal to fetal blood by pinocytosis
e) secretes oestradiol
TFFTT
Oxytocin:
a) stimulates production of milk
b) stimulates ejection of milk
c) release is stimulated by dilatation of the cervix
d) is synthesised in the anterior pituitary
e) produces more powerful uterine contraction in the presence of progesterone
FTTFF
Aldosterone:
a) production increases with a fall in plasma osmolality
b) production decreases with a fall in blood volume
c) production decreases with a rise in plasma renin level
d) increases urinary potassium excretion
e) may be produced by tumours of the adrenal cortex
FFFTT
