Human Immune System

Question 1

Innate immunity

Answer 1

Broad defenses against many kinds of pathogens

Question 2

Barrier defenses

Answer 2

Physical barriers to success of pathogens

Includes mucus, skin oil, saliva, tears, and epithelial linings

Question 3

Innate defenses

Answer 3

Cellular systems to stop pathogens

Question 4

Neutrophils

Answer 4

Cells that attract to infected tissue and destroy pathogens

Question 5

Macrophages

Answer 5

Large phagocytic cells that eat pathogens

Question 6

Dendritic cells

Answer 6

Stimulate adaptive immunity

Question 7

Eosinophils

Answer 7

Defense cells against multicellular invaders

Question 8

Toll-like receptor (TLR)

Answer 8

Binds to special molecules characteristic of pathogens and not of the body

Question 9

Histamine

Answer 9

Stored in mast cells, released at sites of damage to allow antimicrobial peptides and neutrophils to fix the damage

Question 10

Septic shock

Answer 10

An extreme, systemic inflammatory response that can be fatal

Question 11

Lymphatic system

Answer 11

Circulatory system that sends immune cells throughout the body

Question 12

T cells

Answer 12

Lymphocytes that mature in the thymus

Question 13

B cells

Answer 13

Lymphocytes that mature in the bone marrow

Question 14

Epitope

Answer 14

Portion of antigen that binds to antigen receptor

Question 15

Constant region

Answer 15

Same across all antigen receptors

Question 16

Variable region

Answer 16

Different for every B cell

Question 17

Antigen presentation

Answer 17

Process of host cell displaying antigen fragments using MHC, allowing cells to bind

Question 18

Recombinase

Answer 18

An enzyme that facilitates many combinations of proteins to produce many types of receptors

Question 19

Lymphocyte proliferation

Answer 19

Some become short-lived plasma cells, or effector cells, that act against the pathogen
Others become memory cells which quickly give rise to plasma cells when needed

Question 20

Immunological memory

Answer 20

The use of memory cells to “remember” a disease, induces an intense immune response upon second exposure

Question 21

Humoral response

Answer 21

Occurs in blood and lymph (B cells)

Question 22

Cell-mediated response

Answer 22

Occurs with infected cells (cytotoxic T cells)

Question 23

Helper T cells

Answer 23

Bind to presented antigens from antigen-presenting cells and release cytokines to stimulate T cell proliferation; also activates B and cytotoxic T cells

Question 24

Cytotoxic T cells

Answer 24

Release granzymes to induce apoptosis in the target infected cell

Question 25

B cells

Answer 25

Differentiates into memory B cells and antibody-secreting plasma cells

Question 26

Antibody functions

Answer 26

Neutralization: blocks pathogen from entering a host Opsonization: binding promotes phagocytosis by immune cells Complement: forces a target cell to flood itself and burst

Question 27

Immunization

Answer 27

Takes advantage of immunity by prompting primary response to a pathogen in a weak form, hopefully to encourage a greater response to the actual pathogen

Question 28

Passive immunization

Answer 28

Antibodies transferred from immune animal to non-immune animal

Question 29

Monoclonal antibodies

Answer 29

Large amounts of antibodies prepared from a cloned set of B cells

Question 30

Blood and immune rejection

Answer 30

Blood antibodies can bind to cells from poorly-managed donations of blood, leading to adverse health effects

Question 31

Organs and immune rejection

Answer 31

Immune system attacks MHC molecules from donated tissue, marking these MHC molecules as foreign

Question 32

Allergies

Answer 32

Exaggerated immune responses that come about due to specific allergens; severe cases lead to anaphylactic shock

Question 33

Autoimmune diseases

Answer 33

Body attacks its own molecules

Question 34

Antigenic variation

Answer 34

Changes in epitope expression that can allow new strains of pathogens to dodge immunological memory

Question 35

Latency

Answer 35

Pathogen entering an inactive state concealed from the immune system

Question 36

HIV

Answer 36

A virus that infects cells of the adaptive immune system, also allowing it to hide from the immune system