PATHOLOGY

Detailed explanation-1: -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: -Urine flow Skin, tears and mucus are part of the first line of defence in fighting infection. They help to protect us against invading pathogens.

Detailed explanation-3: -The innate immune system provides the first line of defense, which is divided broadly into two categories – physical/chemical barriers and nonspecific resistance.

Detailed explanation-4: -Epithelial tissue, or skin, is an animal’s first line of defense against environmental challenges. It covers all exterior and interior surfaces of the body, like its cavities, tubes, organs and blood vessels, including the respiratory, reproductive, urogenital and gastrointestinal tracts.