Which of the following is $NOT$ a characteristic property of hemoglobin?

Properties of leucocytes are:
$I$. They are nucleated.
$II$. They are denucleated like $RBC$.
$III$. They are $6000-8000 \; mm^{-3}$ of blood.
$IV$. They are long-lived.
$V$. They are short-lived.
Choose the appropriate option with correct properties.

What are Formed Elements?

The source of thromboplastin in human blood is:

Three children in a family have blood types $O$,$AB$ and $B$ respectively. What are the genotypes of their parents?

The erythropoietic organs of a foetus are . . . . . . and . . . . . . .