What percentage of lymphoid tissue in the human body is constituted by Mucosa-Associated Lymphoid Tissue $(MALT)$ (in $\%$)?

Regarding kidney transplantation,four statements are given below. Select the correct statements.
$i.$ During kidney transplantation,the recipient's immune system is suppressed for a long time.
$ii.$ Cell-mediated immunity is responsible for the rejection of the transplant.
$iii.$ $B$-lymphocytes are responsible for the rejection of the transplant.
$iv.$ Specific interferons are responsible for the acceptance or rejection of the kidney transplant.
Select the correct option:

Interferon is inhibitory to

In the case of a snakebite,what is injected into the patient?

Which type of immunity is acquired by intentionally introducing microorganisms into the body?

Choose the true statements.
$I.$ Innate immunity is accomplished by providing different types of barriers.
$II.$ Acquired immunity is present from birth and is inherited from parents.
$III.$ Sweat,tears,acid in the stomach,and saliva prevent microbial growth.