Pathogens& immune response

Question 1

Primary defences

Answer 1

Prevent pathogens entering the body, non specific

Question 2

diseases

Answer 2

something that alters the normal functioning of the cell

Question 3

pathogen&types

Answer 3

an organism that causes a disease

plants animal and fungi

Question 4

skin as a barrier to infection

Answer 4

physical barrier

produces antimicrobial fluid

Question 5

mucous surfaces as a barrier to infection

Answer 5

genitals, ears, mouth, nose

mucous traps pathogens and contains antimicrobial enzymes

Question 6

blood clotting as a barrier to infection

Answer 6

platelets prevent entry to pathogens

Question 7

T lymphocytes- response

Answer 7

contain specific receptors that bind to antigens on APCs

each T lymphocyte binds to a different antigen

clonal selection

clonal expansion- each T lymphocyte divides to produce clones of itself which carry out different functions

Question 8

T helper cells

Answer 8

produce interleukins to activate B lymphocytes and T killer cells

Question 9

T killer cells

Answer 9

attach to and kill infected cells

Question 10

T regulatory cells

Answer 10

suppress the immune response so other white blood cells don’t attack own body cells

Question 11

B lymphocytes

Answer 11

covered with antibodies that attach to the antigens to form an antigen antibody complex

each B lymphocyte has a different shaped antibody to bind to complementary antigens

clonal selection activated by T helper cells

The activated B lymphocyte divides by mitosis to form plasma cells and memory cells

Question 12

plasma cells

Answer 12

clones of B lymphocytes that secrete a lot of the antibody specific to the foreign antigen

Question 13

how do anitbodies attack infection? (3ways)

Answer 13

neutralisation toxins

agglutinating pathogens

prevention of pathogen binding to human cells

Question 14

agglutinating pathogens

Answer 14

each antibody can bind to two pathogens at once, the pathogens become clumped together and can be engulfed by phagocytes

Question 15

neutralising toxins

Answer 15

anti toxins bund to the toxins produced by pathogens and neutralise them so they arent affecting human cells

Question 16

preventing the pathogen binding to human cells

Answer 16

antibodies bind to antigens so they block the cell surface receptors from binding to own body cells

Question 17

why is the primary response slow?

Answer 17

because there arent many B lymphocytes that can make memory cells or the antibody needed

Question 18

memory T lymphocytes

Answer 18

remembers the specific antigen to recognise it second time round

they divide into the correct type of T lymphocyte

Question 19

memory B lymphocytes

Answer 19

remembers the specific antibodies needed to bind to the antigen

these divide into plasma cells to create the required antibody

Question 20

active immunity

Answer 20

your immune system makes own antibodies after being stimulated by an antigen

requires exposure to the pathogen

Question 21

passive immunity

Answer 21

being given antibodies made by a different organism

Question 22

active natural immunity

Answer 22

becoming immune after catching a disease

measles

Question 23

active artificial immunity

Answer 23

vaccination containing a harmless dose of antigen

Question 24

natural passive immunity

Answer 24

a baby becoming immune after being given antibodies from its mother through the placenta or breast milk

Question 25

passive artificial immunity

Answer 25

becoming immune after being injected with antibodies from someone else blood donations

Question 26

antibiotics

Answer 26

kill or inhibit the growth of bacteria

Question 27

autoimmune disease

Answer 27

When the immune system begins to attack itself examples include: lupus (immune system attacks connective tissue), Rhumatoid arthritis (the immune system attacks joints)