1-0 Overview: The Protective Mechanisms of Immunity

Question 0

Innate immunity

Answer 0

Immune responses mediated by cells and molecules recognizing conserved features of microorganisms and activated immediately on encounter with them.

Question 1

Pathogens

Answer 1

Any microorganism that causes disease.

Question 2

Adaptive immunity

Answer 2

Immune responses mediated by lymphocytes and their products and requiring activation by innate immune mechanisms on first encounter with antigen but acting immediately on subsequent encounters.

Question 3

Lymphocytes

Answer 3

White blood cells bearing highly variable receptors for antigen that circulate in the blood and lymph and are the mediators of adaptive immunity.

Question 4

Immune memory

Answer 4

rapid response of the adaptive immune system to exposure to antigens previously encountered.

Question 5

Complement system

Answer 5

Serum proteins activated directly or indirectly by conserved surface features of microorganisms.

Question 6

Cytokines

Answer 6

Polypeptide signaling molecule that participates in immune responses.

Question 7

Chemokines

Answer 7

Any of a family of closely related small, basic cytokines whose main function is as chemoattractants. The name is a contraction of chemotactic cytokine.

Question 8

Inflammatory response

Answer 8

Release of cytokines by leukocytes at a site of infection causing dilation and increased permeability of blood vessels and the recruitment of immune cells.

Question 9

Inflammatory cytokines

Answer 9

Cytokines that are released by phagocytes of the innate immune system in the presence of microorganisms, or by activated lymphoid cells, and that act on blood vessels and cells of the immune system to induce or amplify immune responses.

Question 10

T lymphocytes

Answer 10

Lymphocytes that mature in the thymus and different classes of which mediate cytotoxic responses against cells infected with viruses, activate B lymphocytes to produce antibodies, and activate phagocytes to ingest and destroy microorganisms.

Question 11

B lymphocytes

Answer 11

Lymphocytes that when activated differentiate into antibody-secreting cells.

Question 12

Antibodies

Answer 12

Highly variable proteins produced by the B lymphocytes of the immune system and that recognize antigen and target it for destruction.

Question 13

Dendritic cells

Answer 13

Specialized cells that ingest debris and infectious agents in the peripheral tissues and migrate to lymphoid tissues where they present fragments of the ingested particles for recognition by T lymphocytes in the activation of adaptive immune responses.

Question 14

Effector T cell

Answer 14

T cells that secrete cytokines (in the case of helper T cells) or deliver cytotoxic signals or effector molecules (in the case of cytotoxic T cells) immediately on activation through recognition of peptide-MHC by their antigen receptors.

Question 15

Lymphoid tissues

Answer 15

specialized tissues in which lymphocytes mature and immune responses are initiated.

Question 16

Antigen

Answer 16

Any molecule or part of a molecule recognized by the variable antigen receptors of lymphocytes.

Question 17

Epitope

Answer 17

Molecular feature of an antigen that is specifically recognized by a lymphocyte or an antibody.