$A$ person with antigens '$B$' in $RBC$ and antibodies '$a$' (anti-$A$) in the plasma belongs to the blood group

Blood clotting in a test tube can be prevented by adding a small amount of ........

State the functions of the following in blood.
$(a)$ Fibrinogen
$(b)$ Globulin
$(c)$ Neutrophils
$(d)$ Lymphocytes

Match the Column $I$ (blood corpuscles) and Column $II$ (stem cells/precursors from which they are formed).

Column $I$ (Blood corpuscles)	Column $II$ (Stem cells/precursors)
$i$. Thrombocytes	$a$. Lymphoid stem cells
$ii$. Granulocytes	$b$. Megakaryocytes
$iii$. Erythrocytes	$c$. Myeloid stem cells
$iv$. Agranulocytes	$d$. Reticulocytes

Choose the correct option given below.

Globulins are $.......$.

Which one of the following cells secrete heparin,histamine and serotonin?