PATHOLOGY

Detailed explanation-1: -Skin is a barrier that serves as one of the body’s first lines of defense against harmful microbes. Specialized immune cells within skin tissue help to fight invading organisms. Yet the skin hosts diverse communities of beneficial bacteria, collectively known as the skin microbiota.

Detailed explanation-2: -These barriers form the first line of defense in the immune response. Examples of innate immunity include: Cough reflex. Enzymes in tears and skin oils.

Detailed explanation-3: -The first line of defense is physical and chemical barriers that cover the body surfaces such as the skin, mucous membranes, saliva, hair, and bodily excretions. The second line of defense is nonspecific immune cells and chemicals that work to fight pathogens.

Detailed explanation-4: -The first line of defense against infection are the surface barriers that prevent the entry of pathogens into the body. The second line of defense are the non-specific phagocytes and other internal mechanisms that comprise innate immunity.