IMMUNOLOGY

Detailed explanation-1: -The innate immune responses are the first line of defense against invading pathogens. They are also required to initiate specific adaptive immune responses. Innate immune responses rely on the body’s ability to recognize conserved features of pathogens that are not present in the uninfected host.

Detailed explanation-2: -All living organisms are continuously exposed to substances that are capable of causing them harm. Most organisms protect themselves against such substances in more than one way—with physical barriers, for example, or with chemicals that repel or kill invaders.

Detailed explanation-3: -Immune responses require the coordinated action of leukocytes that travel the body to eliminate threats posed by trauma, infection, toxins, and cancer. Leukocytes communicate via direct contact and via production and receipt of soluble proteins and intercellular messenger proteins called cytokines.

Detailed explanation-4: -The second line of defense against non-self pathogens is called adaptive immune response. Adaptive immunity is also referred to as acquired immunity or specific immunity and is only found in vertebrates.

Detailed explanation-5: -Specific defense (sometimes called adaptive immunity) recognizes and coordinates attacks against specific pathogens. The system can also remember pathogens and produce a powerful response the next time a pathogen enters the body.