Name the major site where $RBCs$ are formed.

$A$ person with $AB$ blood group is called a universal recipient because .....

Which of the following vitamins is needed for the coagulation of blood?

In a normal healthy person,if the total number of $WBCs$ is about $9000 / mm^3$,then the number of Agranulocytes is about . . . . . . $/ mm^3$ of blood.

In which one of the following human organs are the old and worn-out RBCs destroyed?

One of the factors required for the maturation of erythrocytes is . . . . . . .