MRCOG 1 Free MCQS1

by **mandible** Wed Feb 24, 2010 3:06 pm

Haematology : MCQ
Question 1: Plasmin
T Is a proteolytic enzyme
T Is formed from plasminogen
T Digests fibrin
T Digests fibrinogen

Question 2: In the investigation of bleeding disorders
F The bleeding time assesses the intrinsic coagulation pathway
T The normal bleeding time is 3-10 minutes
T Blood for coagulation studies is collected into citrate solution to prevent
T The prothrombin time is prolonged in abnormalities of the extrinsic pathway

Question 3: With respect to iron metabolism
F The body contains about 40g of iron
F Most of the iron in the body is contained in ferritin
F Iron is transported in plasma as ferritin
F Haemosiderin is the main form in which iron is stored in tissues

Question 4: The following mechanisms are important in haemostasis
T Vascular spasm
T Formation of platelet plug
T Formation of blood clot
T Organisation of blood clot

Question 5: Blood coagulation
F Through the extrinsic pathway is initiated by contact of blood with a
negatively charged surface
F Through the intrinsic pathway does not occur outside the body
T Through the extrinsic pathway is initiated by tissue damage
T Through the extrinsic pathway is initiated by the release of tissue
thromboplastin

Question 6: Erythrocytes
F Are not produced in the fetal liver
F Are produced by the liver during the first 5 years of life
T Are produced by the bone marrow of almost every bone in the body during
the first 5 years of life
T Are produced by the bone marrow of the ribs, sternum and vertebrae in
Adults

Question 7: Blood coagulation
T Through the intrinsic and extrinsic pathways results in the activation of
Factor X
F Results from the conversion of thrombin to prothrombin
T Results from the conversion of fibrinogen to fibrin
F Can occur in the absence of calcium

Question 8: With respect to iron metabolism
T Antacids reduce iron absorption
T Heme iron is better absorbed than non-heme iron
T Ferrous iron (2+) is better absorbed than ferric iron (3+)
F The majority of iron absorption occurs in the terminal ileum

Question 9: With respect to Rhesus blood group
F There are three different Rhesus factors
F An individual with the C antigen can also have the c antigen
T An individual with the D antigen cannot have the d antigen
T The type D antigen is the most antigenic of all the Rhesus antigens

Question 10: Erythrocyte
T Production is stimulated by anaemia due to blood loss
F Production is impaired at high altitude
F Production is stimulated by hyperoxia
T Production is stimulated by erythropoietin

Question 11: With respect to Rhesus blood group
F Rhesus positive individuals have the d antigen
F The C and E antigens do not cause transfusion reactions
F 85% of Caucasians are Rhesus negative
F After injection of the D antigen into Rhesus negative individuals, the peak
concentration of anti-D antibodies is attained within 3-6 weeks

Question 12: Erythrocytes
T Are biconcave discs
F Have an average diameter of 80 microns
F Have a mean cell volume of 60 fl
T Have an average life span of 120 days

Question 13: The following are vitamin K dependent clotting factors
T Prothrombin
F Factor XII
T Factor VII
T Factor X

Question 14: The following are vitamin K dependent clotting factors
T Factor IX
F Factor XI
F Fibrinogen
F Plasminogen

Question 15: With respect to Rhesus blood group
F Transfusion of Rhesus incompatible blood into a non-sensitized individual
causes an immediate transfusion reaction
F The first pregnancy is never affected by Rhesus disease
F The child of a Rhesus positive father and a Rhesus negative mother must
be Rhesus positive
T The child of a Rhesus negative mother and a Rhesus negative father
cannot be Rhesus positive

Neuromuscular physiology: MCQ
Question 1: With respect to active transport
F The sodium-potassium pump transfers three sodium ions from the
extracellular to the intracellular space
F The sodium-potassium pump transfers two potassium ions from the
intracellular to the extracellular space
F The sodium-potassium pump hydrolyses one molecule of ATP per sodium
ion transported
T The sodium-potassium pump is electrogenic

Question 2: Skeletal muscles
T Are multinucleated cells
F Contain thick actin and thin myosin filaments
T Have light (I) bands which contain actin filaments only
F Have dark (A) bands which contain myosin filaments only

Question 3: With respect to the transfer of solutes across cell membranes|
F Lipid soluble solutes require the presence of carrier proteins for transfer
across the cell membrane
F Hydrogen ions diffuse readily across the cell membrane
T Protein channels in membranes are specific for the transport of specific
solutes
T Protein channels can be voltage-gated

Question 4: Cardiac muscle
T Is striated
F Has myosin but not actin filaments
F Has multinucleated cells
F Cells are connected to other cardiac muscle cells at gap junctions

Question 5: Cardiac muscle
F Of the atria is continuous with that of the ventricles
T Forms a syncytium
FStimulation of a single atrial cardiac muscle would cause an action potential
to travel through the entire atrial and ventricular muscle mass
T Have intercalated discs

Question 6: With respect to action potentials
F Salutatory conduction occurs in unmyelinated fibres
T There is an absolute and a relative refractory period
F Transmission occurs at the same speed in myelinated and unmyelinated
neurons
F The potential changes in size and shape as they spread across the
membrane
Question 7: With respect to action potentials
F Transmission occurs at the same speed in small and large neurons
F Depolarisation is caused by increased permeability to potassium ions
F The membrane potential always becomes positive during depolarisation
F Repolarisation is caused by increased permeability to sodium ions
Question 8: Action potentials
T Are rapid changes in membrane potential
F Begin with a change of the positive resting potential to a negative potential
F Are propagated in one direction only
F Are not delayed at synapses
Question 9: During excitation and contraction of skeletal muscle fibres
T Excitation of the T-tubules results in the release of calcium from the
sarcoplasmic reticulum
F Calcium binds to and activates tropomyosin
T Calcium is pumped into the sarcoplasmic reticulum to initiate muscle
relaxation
T Acetylcholine is released at the motor end plate
Question 10: With respect to action potentials
T Depolarisation is caused by activation of voltage gated sodium channels
T Would not occur until the membrane potential rises above a threshold
T Once established travel over the entire membrane
F Activation of potassium channels is responsible for the plateau in the action
potential of cardiac muscle
Question 11: With respect to smooth muscle
F Smooth muscle contains actin but not myosin
F The membrane potential is more negative than that of skeletal muscle
F Smooth muscle action potential is mainly due to activation of voltage gated
sodium channels
F Extrinsic stimulation is always required for the generation of action potential
Question 12: With respect to active transport
T The sodium-potasium pump is important in regulating cell volume
F The calcium pump transfers calcium from the extracellular to the
intracellular space
F Active transport is not saturable
F Carrier proteins involved in secondary active transport hydrolyse ATP to
ADP
Question 13: With respect to smooth muscle
T Action potential can be initiated by stretch
F Calcium is pumped into the sarcoplasmic reticulum to bring about muscle
relaxation
T Intracellular calcium binds to calmodulin to initiate muscle contraction
F There are specialised neuro-muscular junctions
Question 14: The following are important in setting the resting membrane potential of neurons
T The activity of the Na / K pump
T Potassium diffusion across the cell membrane
T Sodium diffusion across the cell membrane
T The presence of impermeant anions within the cell
Question 15: Skeletal muscles
F Have actin filaments which have cross-bridges
F Have myosin filaments which are attached to the Z-disc
THave sarcomeres which are the portions of the muscle between Z discs
T In the resting state, the actin filaments completely overlap the myosin
Filaments
Cardiovascular physiology MCQ S

Question 1: With respect to action potential in the sino-atrial node
F The resting membrane potential is more negative than for non-conducting
cardiac muscle
FDepolarisation is caused by activation of fast voltage gated sodium
channels
F There is dependence on vagal nerve stimulation for the generation of
action potentials
T Repolarisation is caused by increased potassium permeability
Question 2: During the cardiac cycle
F The T wave occurs after the end of ventricular contraction
T The a wave in the atrial pressure profile is caused by atrial contraction
F The c wave in the atrial pressure profile is caused by opening of the
atrio-ventricular valve
T The v wave in the atrial pressure profile is caused by venous return into the
Question 3: During the cardiac cycle
F Atrial contraction occurs during systole
T The P wave of the electrocardiogram represents atrial depolarisation
F The QRS complex represents ventricular repolarisation
F The T wave represents ventricular depolarisation
Question 4: Vasodilatation is caused by
F Increased pH
T Increased osmolarity
T Increased CO2 concentration
F Increased oxygen tension
Question 5: The following are associated with a decrease in cardiac output
F Increased blood volume
T Acute venous dilatation
T Venous obstruction
F Blood pressure of 160/100
Question 6: During the cardiac cycle
T The v wave in the atrial pressure profile is caused by venous return into the
atrium
T The notch in the aortic pressure profile is caused by closure of the aortic
valve
F The first heart sound is caused by opening of the atrio-ventricular valves
T The second heart sound is caused by closure of the aortic and pulmonary
Valves

Question 7: With respect to the conducting system of the heart
F The refractory period of the atrioventricular node is shorter than for normal
cardiac muscle fibres
F The sinoatrial node has an intrinsic rhythmic rate of 40-60 per minute
T The atrioventricular node has an intrinsic rhythmic rate of 40-60 per minute
T The Purkinje fibres have an intrinsic rhythmic rate of 15-40 per minute
Question 8: With respect to autonomic control of the heart
F Vagal stimulation has no effect on the rate of the rhythm of the sinoatrial
node
T Vagal stimulation decreases the excitability of the atrio-ventricular
junctional fibres
T Sympathetic stimulation increases the rate of the rhythm of the sinoatrial
node
F Sympathetic stimulation decreases the strength of myocardial contraction
Question 9: The following are important mechanisms in the short-term
maintenance of arterial pressure following haemorrhage
T Peripheral vasoconstriction
F Increased fluid retention by the kidneys
T Increased heart rate
F Increased venous return
Question 10: The following are produced locally in tissues and regulate
perfusion
T Prostaglandins
T Serotonin
F Adrenaline
F Noradrenaline
Question 11: With respect to the conducting system of the heart
T The sinoatrial node is the natural pacemaker
T Impulses are conducted from the sinoatrial node to the atrioventricular
node by three internodal pathways
F Impulses are conducted from the right atrium to the left atrium by the
Purkinje fibres
T There is a delay in the conduction of cardiac impulses at the atrioventricular
node
Question 12: During the cardiac cycle
F Pressure in the left ventricle must rise above 120mmHg to cause opening
of the aortic valve
F The period of rapid ejection occupies the first 70% of ventricular ejection
time
T The normal PR interval is about 0.16s
F The QT interval is the duration of ventricular relaxation
Question 13: Mean arterial pressure
T Is the average arterial pressure over a cardiac cycle
F Can be calculated from ½ (systolic minus diastolic pressure)
T Can be calculated from diastolic pressure + 1/3(pulse pressure)
F Can be calculated from the cardiac output X total peripheral resistance
Question 14: The following are associated with a decrease in cardiac output
F Pregnancy
F Anaemia
T Haemorrhage
F Hyperthyroidism
Question 15: During the cardiac cycle
F Blood flows into the atria only during atrial diastole
F Atrial contraction contributes 70% to ventricular filling
F Blood flows from the atria into the ventricles during systole
F Ventricular ejection occurs during the period of isometric contraction

Gastrointestinal physiology MCQ
Question 1: Gastric secretion
T Is inhibited by cholecystokinin
T Is inhibited by gastric inhibitory peptide
F Is stimulated by sympathetic stimulation
F Is stimulated by nicotinic agonists
Question 2: Gastric secretion
T Occurring during the cephalic phase is mainly under vagal control
F Occurring during the gastric phase is mainly caused by secretin stimulation
T Occurring during the intestinal phase is caused by gastrin secreted by the
duodenum
T Is inhibited by secretin
Question 3: During swallowing
F Afferent impulses of the swallowing reflex travel in the facial nerve
T Afferent impulses of the swallowing reflex travel in the trigerminal and
glossopharyngeal nerves
T Motor impulses from the swallowing centre travel in the trigerminal nerve
T Motor impulses from the swallowing centre travel in the glossopharyngeal
and vagus nerves
Question 4: With respect to the autonomic control of the gastrointestinal tract
F Sympathetic post-ganglionic fibres originate in the Meissner’s plexus
F Sympsthetic post-ganglionic fibres originate in the myenteric plexus
F Sympathetic pre-ganglionic fibres originate in the sympathetic chain
F Sympathetic pre-ganglionic neurons secrete noradrenaline
Question 5: Bile salts
T Are synthesised from cholesterol
F Contain bilirubin
F Increase the surface tension in fat particles in the small intestine
T Form micelles with lipids in the small intestine
Question 6: Gastric secretion
T Is stimulated by vagal stimulation
F Is inhibited by gastrin
T Is stimulated by histamine
F Is stimulated when the pH within the stomach is < 2.0
Question 7: With respect to the regulation of pancreatic secretion
F Secretin is secreted when the pH of duodenal contents is > 4.5
T Cholecystokinin is secreted by the mucosa of the small intestine
F Cholecystokinin stimulates bicarbonate secretion by the pancreas
F Gastrin inhibits pancreatic secretion
Question 8: Bile salts
T Play an important role in the absorption of vitamin A
F Play an important role in the absorption of folate
T Play an important role in the absorption of vitamin K
T Have an entero-hepatic circulation
True False
Question 9: The oxyntic cells of the stomach secrete
F Pepsin
T Intrinsic factor
F Gastrin
F Pepsinogen
Question 10: Cholecystokinin
F Is a glycoprotein
F Is secreted mainly by the terminal ileum
T Stimulates contraction of the gall bladder
F Relaxes the sphincter of Oddi
Question 11: With respect to the autonomic control of the gastrointestinal tract
T Parasympathetic stimulation causes increased motility
T Sympathetic post-ganglionic neurons secrete noradrenaline
F Sympathetic stimulation increases gut motility
T Sympathetic stimulation decreases secretory activity
Question 12: Bile
T Is secreted by hepatocytes
T Is concentrated by the gall bladder
T Is rich in cholesterol
F Is essential for protein digestion and absorption
Question 13: Gastric emptying
F Is stimulated by secretin
F Is stimulated by cholecystokinin
T Is inhibited by gastric inhibitory peptide
T Is inhibited by sympathetic stimulation
Question 14: Saliva
T Has a higher potassium cocentration than plasma
F Has a higher chloride concentration than plasma
T Secretion is stimulated by parasympathetic stimulation
T Contains mucus
Question 15: With respect to the autonomic control of the gastrointestinal tract
F Parasympsthetic pre-ganglionic fibres originate in the Meissner’s plexus
True False
T Parasympathetic post-ganglionic fibres originate in the myenteric plexus
T Parasympathetic post-ganglionic fibres secrete acetylcholine
T Parasympathetic stimulation causes increased secretion

Acid-base & renal function MCQ Test
Question 1: Angiotensin II
F Is a decapeptide
T Is produced from angiotensin I in the lungs
T Is a vasoconstrictor
T Stimulates aldosterone secretion
Question 2: The following are recognised causes of metabolic acidosis with increased anion gap
T Diabetic ketoacidosis
T Starvation
F Hyperparathyroidism
F Diarrhoea
Question 3: Metabolic acidosis
T Caused by severe diarrhoea is associated with a normal anion gap
T Caused by renal tubular acidosis is associated with a normal anion gap
T Caused by lactic acidosis is associated with an increase in the anion gap
F Caused by diabetic ketoacidosis is associated with a decrease in the anion
gap
Question 4: The metabolism of the following amino acids results in the
production of acids
T Hystidine
F Aspartate
F Glutamate
F Alanine
Question 5: Respiratory alkalosis
T Occurs in hyperventilation
F Occurs in normal pregnancy
T May occur in type I respiratory failure
F May occur in type II respiratory failure
Question 6: A 20 year old woman has the following arterial blood results: pH= 7.49, PCO2 = 47mmHg, [HCO3-] = 35mM, Oxygen saturation = 98% on air.Her plasma potassium concentration is 2.5mM
F There is a respiratory alkalosis
T There is a metabolic alkalosis
F Her urine is likely to be alkaline
F Pulmonary embolism is a likely diagnosis
Question 7: With respect to the renal regulation of acid-base balance
F Ammonium ions are mainly produced in the loop of Henle
T Glutamine metabolism by the kidneys results in bicarbonate production
T Ammonia production by the kidneys is increased in acidosis
T Secreted hydrogen ions are buffered by the phosphate buffer system in
tubular fluid
Question 8: Arterial blood gas analysis from a 20 year old woman shows: pH= 7.36; PCO2 = 32mmHg, [HCO3-] = 17mM, Oxygen saturation = 99% on air
F Pulmonary embolism is a likely diagnosis
F She is acidotic
T Aspirin overdose is a possible diagnosis
F The anion gap is likely to be decreased
Question 9: With respect to the bicarbonate buffer system
T Within extracellular fluid is made up of carbonic acid and sodium
bicarbonate
T Within intracellular fluid is made up of carbonic acid and potassium
bicarbonate
T The majority of carbonic acid exists as dissolved carbon dioxide
F The pH is proportional to the log of the bicarbonate ion concentration
Question 10: With respect to renal function
T Urea clearance is proportional to urinary flow rate
F Urea clearance is proportional to plasma urea concentration
F Urea clearance is inversely proportional to urinary urea concentration
F Glomerular filtration rate can be determined using creatinine as a marker
Question 11: The following are recognised causes of metabolic alkalosis
T Vomiting
F Starvation
T Diuretic therapy
F Hyperparathyroidism
Question 12: With respect to acid – base status
F The pH is calculated from (log of hydrogen ion concentration)
True False
F The pH of arterial blood is 7.35
F The pH of venous blood is 7.4
T pH of interstitial fluid is 7.35
Question 13: Respiratory acidosis
F Occurs in type I respiratory failure
F If chronic, is associated with a fall in plasma bicarbonate concentration
T Occurs in chronic bronchitis
F Is associated with a high arterial PO2
Question 14: The following are recognised causes of metabolic acidosis with a normal anion gap
F Salicylate poisoning
F Starvation
T Diarrhoea
T Pancreatic fistulae
Question 15: A 34 year old woman has the following arterial blood gas
results: pH = 7.34, [HCO3-] = 17mM, PCO2 = 30mmHg
F Pulmonary embolism is a likely diagnosis
F She has a respiratory acidosis
T She has a metabolic acidosis
T There is a respiratory compensation to a metabolic acidosis

Adaptation to pregnancy MCQ

Question 1: The following changes occur in the cardiovascular system
during pregnancy and lactation
T 40% increase in cardiac output by 12 weeks gestation
F Decreased cardiac output in the third trimester
F Decreased cardiac output during labour
F Increased cardiac output in association with breastfeeding
Question 2: Pregnancy is associated with
F Increased uric acid reabsorption from the renal tubules
F Increased plasma uric acid concentration
T Increased glucose filtration into glomerular fluid
F Decreased urinary amino acid excretion
Question 3: Normal pregnancy is associated with
T A rise in factor VIII concentration in haemophilia carriers
T A rise in von Willebrand factor concentration in women with von Willebrand
disease
F Increased anti-thrombin III concentrations
F Decreased protein C concentration
Question 4: Normal pregnancy is associated with
F Decreased fibrinogen concentration
T Increased erythrocyte sedimentation rate
T Increased factor VIII concentrations
F Decreased von Willebrand factor
Question 5: During pregnancy
T Minute ventilation is increased
F Tidal volume is decreased
F Respiratory rate is decreased
T There is a fall in arterial PCO2
Question 6: The following changes occur in the fetal circulation at birth
T Closure of the foramen ovale
F Increased resistance in the pulmonary arteries
F Decreased blood flow into the pulmonary arteries
F Decreased pressure in the left atrium
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