How does skin protect us from germs?
Perhaps the most obvious way skin protects us from germs is simply to serve as a barrier between what we touch and what is allowed within the body. Most germs are unable to penetrate the skin unless there is damage to the surface such as a scratch or cut. The living skin cells are also able to make antimicrobial proteins called defensins which helped destroy the cell walls of bacteria. The constant renewal of skin cells also helps remove bacteria attached to the skin surface as these cells flake off. Sebaceous glands produce an oily substance which helps lubricate the skin. This substance (called sebum) helps keep the skin from drying out but also inhibits the growth of bacteria.
