Lymph glands and nodes help to

The spleen is a large bean-shaped organ which primarily acts as a filter of the blood by trapping blood-borne microorganisms. Which of the following statements is correct regarding the spleen?

Match the following columns:

Column-$I$	Column-$II$
$1.$ Saliva and tears	$a.$ Cytokine barrier
$2.$ Mucus coating	$b.$ Cellular barrier
$3.$ $PMNL$	$c.$ Physiological barrier
$4.$ Interferons	$d.$ Physical barrier

Antiserum contains

In vaccination,inactive or dead antigens are introduced into the body. What type of immunity is this?

Acquired immunity is mediated by which of the following?