ANATOMY

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: -The innate immune system functions as the first line of host defense against pathogens, including SARS-CoV-2. Innate immune responses limit viral entry, translation, replication and assembly, help identify and remove infected cells and coordinate and accelerate the development of adaptive immunity.

Detailed explanation-3: -The immune system includes three lines of defense against foreign invaders: physical and chemical barriers, nonspecific resistance, and specific resistance.

Detailed explanation-4: -The skin prevents the entry of microbes into the body. Skin secretes oil from the oil glands and sweat from the sweat glands that kill the microbes. Thus, skin acts as a physical barrier and prevents various infections.

Detailed explanation-5: -The epidermis, the outermost layer of the skin, is a physical barrier against pathogens.