IMMUNOLOGY

Detailed explanation-1: -Protection offered by the skin and mucous membranes All outer and inner surfaces of the human body a key part of the innate immune system. The closed surface of the skin and of all mucous membranes already forms a physical barrier against germs, which protects them from entering.

Detailed explanation-2: -Chemical barriers also protect against infection by pathogens. They destroy pathogens on the outer body surface, at body openings, and on inner body linings. Sweat, mucus, tears, saliva, and breastmilk all contain antimicrobial substances (such as the enzyme lysozyme) that kill pathogens, especially bacteria.

Detailed explanation-3: -NON SPECIFIC DEFENSES: Skin and Mucous membranes, antimicrobial chemicals, natural killer cells, phagocytosis, inflammation and fever.

Detailed explanation-4: -The innate immune system consists first of physical and chemical barriers to infection including the skin and mucous membranes and their secretions, ciliated surfaces, and body hairs.

Detailed explanation-5: -The first line of defence is non-specific and aims to stop microbes from entering the body. The skin and mucous membranes act as a physical barrier preventing penetration by microbes. If the skin is cut then the blood produces a clot which seals the wound and prevents microbes from entering.