Features of innate immunity A1E ?

Ans. is 'a' i.e., Recognised foreign antigen in blood The physiological function of the immune system is to protect individuals from infectious pathogens. The mechasnisms that are responsible for this protection fall into two broad categories ? Innate (Native Immunity) o It is the resistance to infections which an individual possesses by viue of his genetic and constitutional make up. o It is the first line of defence against infectious agents. o It is present since bih and is found both in inveebrates and veebrates. o It is not affected by prior contact with microorganisms or immunization ie antigen exposure is not required for its development. o There is no immunological memory. o It is nonspecific, it is active against a wide range of infectious agents. o Sometimes the innate immunity itself is able to control the infection on its own but sometimes the defence of the innate immunity is breached, then the adaptive immunity is called into action. Impoant components of the innate Immune system. Cells Macrophages, Dendritic cells, NK cells, NK-T cells, Neutrophils, Eosinophils, mast cells, basophils, epithelial cells. Complement components Classical and alternative pathway. Antimicrobial peptides Defensins, cathelin, probiatics. 4.Pattern recognition receptors 5.Cytokines. Adaptive (Acquired) immunity o Adaptive immunity is found only in veebrates o It is based on the generation of antigen receptors on T and B lymphocytes by genn line gene rearrangements. o It is specific. o It is developed as a result of an antigenic stimulus (Immunological priming). o It provides immunological memory; subsequent antigen exposure leads to more rapid and vigorous immune responses. o The adaptive immune system consist of dual limbs of cellular and humoral immunity. Component of the adaptive immune system. T cells 3. Antibody B cells 4. Plasma cells