Newborn babies generally do not shiver despite low temperatures because of:

Match the following:
Types of leucocytes | Function
$A.$ Neutrophils | $1.$ Heparin and histamine secretion
$B.$ Basophils | $2.$ Antibodies formation
$C.$ Acidophils | $3.$ Scavenger
$D.$ Monocytes | $4.$ Phagocytes
$E.$ Lymphocytes | $5.$ Antiallergic and healing of wounds
The correct pairing sequence is:

$A$: $A$ portal system consists of veins that start from capillaries and end into capillaries.
$R$: All vertebrates have a hepatic portal system.

Which of the following statements are wrong?
$(i)$ Leucocytes disintegrate in the spleen and liver.
$(ii)$ $RBC$,$WBC$ and blood platelets are produced by bone marrow.
$(iii)$ Neutrophils bring about destruction and detoxification of toxins of protein origin.
$(iv)$ The important function of lymphocytes is to produce antibodies.

Select the correct option:
$(1)$ $AB / O$ blood group is the universal recipient.
$(2)$ Mitral valve / Semilunar valve is located between the atrium and the ventricle.

Which of the following vertebrate organs receives only oxygenated blood?