Structural Organisation In Animals Question 321
Assertion : Thrombin is necessary to initiate blood coagulation. Reason : Thrombin helps in the formation of fibrin.
Options:
A) If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B) If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C) If the assertion is true but the reason is false
D) If both the assertion and reason are false
Show Answer
Answer:
Correct Answer: C
Solution:
Blood coagulation is brought about by the hydrolysis of soluble protein fibrinogen to insoluble fibrin.
This reaction is catalysed by the enzyme thromboplastin.
Thrombin occurs in normal blood as an inactive precursor called prothrombin which is activated to thrombin by the action of another enzyme called prothrombinase before blood coagulation starts.
Thromboplastins are the coagulation promoting substances released from clumped platelets and damaged tissue, which helps in the formation of the enzyme prothrombinase.
BETA
