Body Fluids MCQ for MRCP USMLE AMC MRCS – Part 2
4. Breakdown of erythrocytes in the body
A. Occurs when they are 6–8 weeks old.
B. Takes place in the reticuloendothelial system.
C. Yields iron, most of which is excreted in the urine.
D. Yields bilirubin which is carried by plasma protein to the liver.
E. Is required for the synthesis of bile salts.
Answer to the Question No 4
A. False. The normal erythrocyte lifespan is 16–18 weeks.
B. True. The RES (Reticuloendothelial system) removes effete RBCs from the circulation.
C. False. Most of the iron is retained for further use.
D. True. The protein makes the bilirubin relatively water-soluble.
E. False. Bile salts are synthesised from sterols in the liver.
5. A person with group A blood
A. Has anti-B antibody in the plasma.
B. May have the genotype AB.
C. May have a parent with group O blood.
D. May have children with group A or group O blood only.
E. Whose partner is also A can only have children of groups A or O.
Answer to the Question No 5
A. True. This appears about the time of birth.
B. False. This would make them blood group AB.
C. True. They could inherit an A gene from the other parent to give genotype AO.
D. False. B or AB are possible depending on the partner’s genes.
E. True. In this case, neither parent has the B gene.
6. Blood platelets assist in arresting bleeding by
A. Releasing factors promoting blood clotting.
B. Adhering together to form plugs when exposed to collagen.
C. Liberating high concentrations of calcium.
D. Releasing factors causing vasoconstriction.
E. Inhibiting ﬁbrinolysis by blocking the conversion of plasminogen to plasmin.
Answer to the Question No 6
A. True. e.g. Thromboplastin, part of the intrinsic pathway.
B. True. Vascular leaks are sealed by such platelet plugs.
C. False. High Ca2 levels are not needed for haemostasis; normal levels are adequate.
D. True. e.g. Serotonin (5-hydroxytryptamine).
E. False Serotonin from platelets can release vascular plasminogen activators.
7. Plasma bilirubin
A. Is a steroid pigment.
B. Is converted to biliverdin in the liver.
C. Does not normally cross cerebral capillary walls.
D. Is freely ﬁltered in the renal glomerulus.
E. Is sensitive to light.
Answer to the Question No 7
A. False. It is a porphyrin pigment derived from haem.
B. False. Bilirubin is derived from biliverdin formed from haem, not the other way about.
C. True. The ‘blood–brain barrier’ normally prevents bilirubin entering brain tissue.
D. False. The bilirubin–protein complex is too large to pass the glomerular ﬁlter.
E. True. Light converts bilirubin to lumirubin which is excreted more rapidly; Phototherapy may be used in the treatment of haemolytic jaundice in children.