FIRST MCQ TEST ANSWER - PART II

6. Microscopic appearance of chronic venous congestion of liver:

a.       Periportal necrosis

b.      Centilobular necrosis

c.       Bridging necrosis

d.      All the above

 Blood supply to the liver is from hepatic artery and portal vein which are located in the portal triad. The centrilobular region, because it is far away from the portal triad receives less oxygen supply than the periportal region which is near to the portal triad and receives more oxygen supply.

During chronic venous congestion (CVC) there is accumulation of venous blood. Since the venous blood is deoxygenated liver undergoes hypoxic injury. The centrilobular region which normally itself receives less oxygen supply is more affected now and undergoes necrosis. Thus centrilobular necrosis occurs in chronic venous congestion of liver.

During CVC, the periportal region also undergoes hypoxic injury because of accumulation of venous blood. However since the periportal region is close to hepatic artery it receives some oxygen, escapes from necrosis but undergoes fatty change alone. 

So the correct answer is option B

7. Which among the following tissues is more prone for infarction?

a.       Lung

b.      Kidney

c.       Liver

d.      Forearm

 Lung, liver and forearm have dual blood supply. (Find out how and enter the answer in comments box) . so even if one blood supply is blocked the other will still supply blood and the organ will survive. However kidney has blood supply only from renal artery. Because of the single blood supply kidney is more prone for infarction.

So the correct answer is option B

8. The most common organisms that cause septic shock is

a.       Gram positive bacteria

b.      Gram negative bacteria

c.       Fungi

d.      Parasites

 The correct answer is option A - gram positive bacteria

9. Chokes and bends are associated with

a.       Fat embolism

b.      Air embolism

c.       Marrow embolism

d.      Amniotic fluid embolism

 The correct answer is option B - Air embolism

10. Primary hemostasis is

a.       The conversion of fibrin to fibrinogen

b.      The conversion of fibrinogen to fibrin

c.       The formation of platelet plug

d.      None of the above

 The correct answer is option C - the formation of platelet plug. This has already been explained in MCQ answers - Part 1.