IMMUNOLOGY

Detailed explanation-1: -Mechanical barriers-which include the skin, mucous membranes, and fluids such as tears and urine-physically block pathogens from entering the body. Chemical barriers-such as enzymes in sweat, saliva, and semen-kill pathogens on body surfaces.

Detailed explanation-2: -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-3: -Nonspecific defense mechanisms include the skin, mucous membranes, secretions, excretions, enzymes, inflammatory responses, genetic factors, hormonal responses, nutritional status, behavior patterns, and the presence of other diseases.

Detailed explanation-4: -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.

Detailed explanation-5: -The neutrophils, basophils, eosinophils, and monocytes are all part of a non-specific defense system. This means that the cells are capable of destroying a large variety of bacterial or viral invaders or cellular debris resulting from tissue damage, without specific recognition of which bacterium or viral invader.