The following are some well-known abbreviations, which have been used in this chapter. Expand each one to its full form:

(a) MALT

(b) CMI

(c) AIDS

(d) NACO

(e) HIV

(a) MALT : Mucosal-associated lymphoid tissue.

Explanation: MALT is a significant aggregation of lymphoid tissue which are seen in relation to the mucosa of major tracts, like alimentary canal, respiratory tract etc. They are centres of lymphocytes production.

(b) CMI : Cell-mediated Immunity

Explanation: CMI consists of T-lymphocytes which produce 4 types of T cells. It defends the body against all pathogens including fungi and protozoa. It reacts against transplants. It provides immunity against cancer.

(c) AIDS : Acquired Immuno Deficiency Syndrome

Explanation: AIDS is a disorder of cell mediated immune system of the body. There is a reduction in the number of helper T cells which stimulate antibody production by B-cells. AIDS is caused by HIV(Human Immunodeficiency virus). AIDS was first noticed in USA amongst homosexuals in 1981.

(d) NACO : National AIDS Control Organisation

Explanation: NACO educate people about AIDS.They make people aware of the various ways and precautions to be taken to avoid the chances of AIDS.

(e) HIV : Human Immunodeficiency Virus

Explanation: HIV is a retrovirus that attacks helper T-cells. The HIV virus is spherical in shape. It consists of a single stranded RNA filament segmented into identical filaments and is associated with a reverse transcriptase enzyme.