chapter 5: cell recognition and the immune system

Question 1

What is an infection

Answer 1

an interaction between the pathogen and the bodies defence mechanisms

Question 2

types of lymphocytes response

Answer 2

1. cell mediated response involving T lymphocytes
2. humoral response involving b lymphocytes

Question 3

non specific response

Answer 3

immediate and same for all pathogens

Question 4

specific response

Answer 4

slower and specific to each pathogen

Question 5

non specific examples

Answer 5

1. physical barriers
2. phagocytes

Question 6

specific response examples

Answer 6

1. cell mediated response (t lymphocytes)
2. humoral response (b lymphocytes )

Question 7

how do lymphocytes recognise cell belonging to the body (fetus)

Answer 7

1. in the fetus lymphocytes are colliding with other cells
   2.infection in the fetus is rare
2. lymphocytes will only collide with the body own cells
   4.lymphocytes with the complementary receptors to the bodies cell will be killed or suppressed
3. only lymphocytes that fight foreign material are left

Question 8

how lymphocytes recognise cells belonging to the body (adult)

Answer 8

1. lymphocytes produced in the bone marrow initially only encounter self antigens
2. lymphocytes that show an immune response to the self antigens will undergo cell death (apoptosis)
3. only lymphocytes that respond to foreign material are left

Question 9

types of white blood cells

Answer 9

1. phagocytes
2. lymphocytes

Question 10

phagocytes

Answer 10

ingest and destroy the pathogen by phagocytosis

Question 11

lymphocytes

Answer 11

involved in immune response

Question 12

phagocytes

Answer 12

large particles are engulfed by cells in the vesicles formed form the cell surface membrane

Question 13

phagocytes (role)

Answer 13

carry out phagocytosis

Question 14

phagocytosis process

Answer 14

1.chemical products of pathogens act as attractants for the phagocytes
2. phagocytes have receptors on their cell surface membrane that recognise and attach to chemicals on the surface of the pathogen
3. engulf the pathogen to form a vesicle (phagosome)
lysosomes fuse with the vesicle
lysosomes destroy bacteria by hydrolysis of cell wall

Question 15

the initial response of the body

Answer 15

non- specific

Question 16

immunity

Answer 16

the ability of organisms to resist infections by protecting against disease- causing microorganisms. involves the recognition of antigens

Question 17

what is an antigen

Answer 17

any part of an organism that is recognised as non self. stimulates an innume resposne

Question 18

the presence of a antigen…

Answer 18

triggers the production of an antibody as part of the bodies defence system

Question 19

t lyphocyests can distuinsgust invader cells form normal cells v]becaue

Answer 19

1. phagocytes present a pathogens antigen on its surface
2. body cells invaded by viruses presented its antigen on its surface
3. transplanted cells from the same species have different antigens
4. cancer cells have different antigens

Question 20

cells that present foreign antigens on their surface

Answer 20

antigen presenting cells