CHAPTER 35 IMMUNE SYSTEM

Question 1

pathogens

Answer 1

agents that may cause disease, fungi viruses

Question 2

innate immunity

Answer 2

all animals have from birth

Question 3

adaptive immunity

Answer 3

develops after exposure to agents, involve specific responses to pathogens

Question 4

what are the five types of innate defenses

Answer 4

barrier, phagocytic cells, antimicrobial proteins, natural killer cells, inflammatory response

Question 5

barrier defenses

Answer 5

skin, mucous, respiratory, tears
- the lower pH of skin and the digestive system prevents growth of many bacteria

Question 6

phagocytic cells

Answer 6

• after the thing gets past the barrier defense
• ingestion and break down of foreign substances including bacteria

there are two types of phagocytic WBC in mammals

Question 7

what are the two phagocytic WBC

Answer 7

neutrophils and macrophages

Question 8

neutrophils

Answer 8

circulate blood and are attracted by signals from infected tissue

Question 9

macrophages

Answer 9

are found throughout the body

Question 10

antimicrobial peptides and proteins

Answer 10

pathogens recognition triggers release of peptides that attack pathogens or impede their reproduction
interferons: interfere with viral reproduction
complement system: consists of proteins that are activated by substances on microbe surfaces

Question 11

natural killer cells

Answer 11

cellular innate defenses in vertebrates
destroying virally infected cells, cancerous cells
release chemicals leading to cell death

Question 12

inflammatory response

Answer 12

pain and swelling is brought about to molecules released upon injury or infection
mast cells (detect physical damage) and release histamine which triggers blood vessels to dilate and become more permeable

Question 13

what are the two types of lymphocytes

Answer 13

b cells and t cells

Question 14

b cells

Answer 14

mature in the thymus but move into the brown marrow
- helper b cells can get involved with extracellular agents

Question 15

t cells

Answer 15

mature in the thymus start in brown marrow but stay in the thymus, fights infection in the cell
- can bind to antigen presenting cells
- cytotoxic t cells can kill infected or cancerous cells

Question 16

antigens

Answer 16

substances that can elicit a response from a B or T cell

Question 17

antigen receptor

Answer 17

recognition occurs when a B or T cell bings to an antigen

Question 18

epitope

Answer 18

small accessible part of the antigen that brings to an antigen receptor

Question 19

humoral immune response

Answer 19

b cells and their antibodies help neutralize pathogens in the blood and lymph

Question 20

cell mediated immune responses

Answer 20

specialized t cells destroy infected host cells, binds only to antigen fragments displayed or presented on a host

Question 21

MHC major histocompatibility complex

Answer 21

molecules are host proteins that display the antigen fragments on the cell surface

Question 22

antigen presentation

Answer 22

MHC transports antigen fragments to the cell surface

Question 23

clinal selection

Answer 23

once activated, B or T cell undergoes multiple cell divisions to produce a clone of identical cells

Question 24

effector cells

Answer 24

acts immediately against the antigen

Question 25

memory cells

Answer 25

long lived, give rise to effector cells if the same antigen is encountered again

Question 26

primary immune response

Answer 26

first exposure to a specific antigen

Question 27

secondary response

Answer 27

memory cells facilitate a faster stronger longer response