ANATOMY

Detailed explanation-1: -The first line of defence (or outside defence system) includes physical and chemical barriers that are always ready and prepared to defend the body from infection. These include your skin, tears, mucus, cilia, stomach acid, urine flow, ‘friendly’ bacteria and white blood cells called neutrophils.

Detailed explanation-2: -Nonspecific defenses include anatomic barriers, inhibitors, phagocytosis, fever, inflammation, and IFN.

Detailed explanation-3: -The body’s most important nonspecific defense is the skin, which acts as a physical barrier to keep pathogens out. Even openings in the skin (such as the mouth and eyes) are protected by saliva, mucus, and tears, which contain an enzyme that breaks down bacterial cell walls.

Detailed explanation-4: -These specialized cells and parts of the immune system offer the body protection against disease. This protection is called immunity. Humans have three types of immunity-innate, adaptive, and passive: Innate immunity: Everyone is born with innate (or natural) immunity, a type of general protection.

Detailed explanation-5: -The human body has three primary lines of defense to fight against foreign invaders, including viruses, bacteria, and fungi. The immune system’s three lines of defense include physical and chemical barriers, non-specific innate responses, and specific adaptive responses.