The blood bank of the body or the reservoir where blood is stored and can be mobilized is:

Choose the correct option:
$(1)$ Depolarization of the ventricles induces the $QRS$ / $T$ waves.
$(2)$ Incomplete double circulation is seen in reptiles / birds.

Analogy type questions:
$(1)$ Fish : Single circulation :: Amphibians : ...........
$(2)$ Between right atrium and right ventricle : Tricuspid valve :: Between left atrium and left ventricle : .............

Which of the following is correct regarding blood coagulation?
$I$. Vitamin-$K$ is necessary for the formation of prothrombin.
$II$. Conversion of fibrinogen to fibrin is done by thrombin.
$III$. Conversion of prothrombin to thrombin is done by the enzyme complex prothrombinase.
The option with the correct combination is:

Assertion $A$: In an open circulatory system, the blood volume is high, but the blood pressure is low and irregular.
Reason $R$: In a closed circulatory system, the blood volume is limited, and the blood pressure is high and regular.
Which option is correct for Assertion $A$ and Reason $R$?

Which of the following is the primary site for the breakdown of proteins and the formation of free amino acids?