Name and explain the two types of immune responses in humans.

Explanation

Immune Response. The specific reactivity induced in a host by an antigenic stimulus is known as the immune response.
Primary and Secondary Immune Response. (a) The primary immune response is produced by the first contact of an animal with an antigen. It takes relatively longer time, of low intensity and declines rapidly. (b) The secondary immune response is produced by subsequent exposure of the same host to same antigen. This is also called booster response or anamnistic response. It is due to the memory cells that were produced during the primary response This response occurs more rapidly and lasts much more longer than primary immune response. It is due to this fact that a person who had been suffering from disease like measles, smallpox, or chickenpox becomes immune to subsequent attacks of these diseases.
Immune responses are carried out by two special types of B and T lymphocytes involved in two types of acquired immunity : the humoral or antibody mediated immunity (AMI) and cell- mediated immunity (CMI).