IMMUNOLOGY

Detailed explanation-1: -The innate immune system includes physical and anatomical barriers as well as effector cells, antimicrobial peptides, soluble mediators, and cell receptors (Table 1). Skin and mucosa provide an effective immune barrier between the internal and external environment.

Detailed explanation-2: -Physical barriers: They are mechanical barriers to many microbial pathogens. These are of two types: skin and mucous membrane. 2. Physiological barrier: They include acidity of the stomach, presence of lysozyme, sweat, nasal hair etc.

Detailed explanation-3: -Innate immunity is not caused by an infection or vaccination and depends initially on physical and chemical barriers that work on all pathogens, sometimes called the first line of defense.