chapter 7

Question 1

what are antigens?

Answer 1

any molecule that triggers and immune response

Question 2

what are MHC 1 and MHC 2 proteins?

Answer 2

Both are self-antigens that mark as self so immune doesnt attack, MHC 1 expressed on all cells with nucleus. MHC 2 found on specialised cells of immune system

Question 3

what are allergens?

Answer 3

substances that I.S recognises as non self and initiates immune response. EG : peanuts, dust, pollen

Question 4

what are pathogens?

Answer 4

disease-causing agents, some have cellular structure. EG : parasite, fungi, virus, bacteria, prions

Question 5

what are physical barriers of animals in 1st line of defence?

Answer 5

intact skin, hair (nose/eyes), mucus, cilia

Question 6

what are chemical barriers of animals in 1st line of defence?

Answer 6

stomach acid, lysozymes in tears and saliva, sweat

Question 7

what are microbiological barriers of animals in 1st line of defence?

Answer 7

bacteria on skin, flora on skin and gut

Question 8

what are physical barriers of plants in 1st line of defence?

Answer 8

thorns, thick waxy cuticle, closing of stomata

Question 9

what are chemical barriers of animals in 1st line of defence?

Answer 9

chitinase, phenols, oxalic acid (toxic to digest)

Question 10

what do natural killer cells do ?

Answer 10

degranulate, force cells to undergo apoptosis, pucture and release cytotoxic chemicals, targets viral cells and cancer cells

Question 11

what do mast cells do ?

Answer 11

degranulate, release histamines, important in inflammatory response

Question 12

what do neutrophils do?

Answer 12

engulf pathogens, dies after activation

Question 13

what do eosinphils do?

Answer 13

degranulate cells, release toxins

Question 14

what are intereferons?

Answer 14

interferons signal to neighbouring cells to prepare for infection. they prevent viral spread and DNA replication

Question 15

what happens during opsonisation?

Answer 15

complement proteins stick to outside of pathogen, makinig it easier for I.S cells to recognise.

Question 16

what happens during chemotaxis?

Answer 16

complement proteins attract phagocytes to pathogen

Question 17

what happens during cytolysis?

Answer 17

complement protein initiate MAC (membrane attack complex) where it puntures holes in pathogen, destroying pathogen

Question 18

what are the steps of the inflammatory repsonse?

Answer 18

1) initiation : injured cells release cytokines to attract neutrophils, mast cells degranulate and release histamines

2) vasodilation : blood vessels dilate and become leaky, increased blood flow (redness swelling)

3) migration : phagogytes guided by cytokines to area, complemet proteins come

Question 19

what are macrophages?

Answer 19

engulfs, antigen presenting cell, MHC 2

Question 20

what is clonal selection?

Answer 20

when the B or T cell binds with the pathogen OR MHC 2 marker

Question 21

what is clonal expansion?

Answer 21

rapid mitosis, dividied into many of the cell that has been matched

Question 22

what is clonal differentiation?

Answer 22

B and T cells begin to specialise

Question 23

what are antibodies?

Answer 23

proteins produced by plasma cells during adapive immune response that is specific to an antigen

Question 24

what are the function of antibodies?

Answer 24

agglutination, opsonisation, neutralisation, immobilisation, activate complement proteins

Question 25

what is the process of the humoral. immunity activation?

Answer 25

1) B cells match w/ pathogen or MHC 2 2) B cell confirms w/ T helper cell 3) clonal expansion 4) clonal differentiation (plasma or memory) 5) plasma cells release antibodies, mem cells remain

Question 26

what is the process of the cell mediated immunity?

Answer 26

1) T cell match w/ pathogen or MHC 2 2) T cell confirms w/ T helper 3) clonal expansion 4) clonal dfferentiation (T memory, plasma, cytotoxic) 5) Cyto T leave nymph nodes to site of infrction, and induces apoptosis

Question 27

what is maturation?

Answer 27

learning difference between self and non self cells

Question 28

what is immunological memory?

Answer 28

T and b memory cells allow body to respond to previously encoutered pathogens more quickly and effectively

Question 29

explain the relationship between an allergen, mast cells and histamines

Answer 29

Allergens react with specific antibodies which are attached to mast cells, thereby causing the release of histamines from the mast cells