Chapter 13: The Human Immune System

Question 1

First Line of Nonspecific Defense

Answer 1

A barrier that prevents pathogens from even entering the body. Examples include the skin, mucous membranes, stomach acid, and cilia.

Question 2

Second Line of Nonspecific Defense

Answer 2

Once the microbe enters the body, this is meant to limit the spread of invaders in advance of the specific immune responses.

1. Inflammatory response: histamine triggers larger blood vessels which increase of phagocytes. Prostaglandins promote more blood flow in an area. Chemokines attract phagocytes to the area. Pyrogens increase the body temperature, which speeds up the immune system and makes it harder for microbes to function.
2. Phagocytes: ingest microbes and bacteria.
3. Complement: lysis of invading cells.
4. Interferons: blocks the cell-cell infections.
5. NK cells: destroy infected body cells.

Question 3

Adaptive Immunity

Answer 3

Involves B and T lymphocytes that recognize specific types of different antigens. Involves three steps: recognition, activation, and effector phases.

Recognition: the binding of B and T lymphocytes to the antigen receptors by binding to them.

Activation: binding of antigen receptor to B and T cells cause a rapid cell division, creating effector and memory cells.

Effector: B cells take a humoral response and produce antibodies, whereas T cells use cell-mediated response.

Question 4

T Lymphocytes, T Cells

Answer 4

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