Immune response

Question 1

What are the four stages of the immune response?

Answer 1

Phagocytosis
T-Cells
B-Cells
Antibody production

Question 2

What is a phagocyte?

Answer 2

A type of white blood cell

Question 3

What is phagocytosis?

Answer 3

The engulfment of pathogens

Question 4

What is the first stage of phagocytosis?

Answer 4

The phagocyte recognises the foreign antigens on a pathogen

Question 5

What is the second stage of phagocytosis?

Answer 5

The cytoplasm moves around the pathogen to engulf it, containing it in a phagocytic vacuole

Question 6

What is the third stage of phagocytosis?

Answer 6

A lysosome, which contains lysozyme enzymes, breaks down the bacteria after it fuses with the phagocytic vacuole

Question 7

What does a phagocyte become?

Answer 7

Antigen presenting cell

Question 8

What is a T-Cell?

Answer 8

A type of white blood cell

Question 9

What do t-cells have on their surface and what do they do?

Answer 9

Receptor proteins which bind to complimentary antigens presented to it by phagocytes

Question 10

What are the two types of T cells?

Answer 10

Helper T-cells

Cytotoxic T-cells

Question 11

What do helper T-cells do?

Answer 11

Release chemical signals that activate and stimulate phagocytes

Question 12

What do cytotoxic T-cells do?

Answer 12

Kill abnormal and foreign cells

Activate B-Cells

Question 13

What are B-cells?

Answer 13

A type of white blood cell

Question 14

What are B-cells covered in?

Answer 14

Antibodies

Question 15

What are antibodies?

Answer 15

Proteins that bind to antigens to form an antigen-antibody complex

Question 16

What happens when an antibody on the surface of a B-cell meets a complimentary shaped antigen?

Answer 16

It binds to it

Question 17

What activates B-cells? What is this called?

Answer 17

The formation of an antibody-antigen complex and the chemicals released from the T-cells
Clonal selection

Question 18

What does the activated B-cell divide into?

Answer 18

Plasma cells

Question 19

What are plasma cells identical to?

Answer 19

B-cells

Question 20

What are monoclonal antibodies?

Answer 20

The antibodies which plasma cells secrete loads of which are specific to the antigen

Question 21

What is formed when an antibody binds to an antigen?

Answer 21

Antibody-antigen complex

Question 22

What is agglutination? How does this happen?

Answer 22

Pathogens becoming clumped together

The antibody has two binding sites so two pathogens can bind at the same time

Question 23

What is the same in all antibodies?

Answer 23

Constant region

Question 24

What is different in all antibodies?

Answer 24

Variable region

Question 25

How is one antibody specific to just one antigen?

Answer 25

The variable region has a unique tertiary structure, due to different amino acid structures

Question 26

What forms the cellular response?

Answer 26

The T-cells and other immume system cells they interact with

Question 27

What forms the humoral response?

Answer 27

B-cells, clonal selection and the production of monoclonal antibodies

Question 28

What is the primary response?

Answer 28

When an antigen enters the body for the first time, activating the immune system

Question 29

Is the primary response fast or slow? Why?

Answer 29

Slow | There aren't many B-cells that can make the antibody needed to bind to it

Question 30

What do T-cells and B-cells produce after being exposed to the antigen?

Answer 30

Memory cells

Question 31

What do memory T-cells do during the primary response?

Answer 31

Remember the specific antigen and will recognise it a second time round

Question 32

What do memory B-cells do during the primary response?

Answer 32

Record the specific antibodies needed to bind to the antigen

Question 33

What is the secondary response?

Answer 33

When the same pathogen enters the body again and the immune system produces a quicker and stronger immune response

Question 34

Is the secondary response fast or slow? Why?

Answer 34

Fast | Clonal selection happens faster

Question 35

What do memory B-cells do during the secondary response?

Answer 35

They are activated and divide into plasma cells which produce the right antibody for the antigen

Question 36

What do memory T-cells do during the secondary response?

Answer 36

They are activated and divide into the correct type of T-cells to kill the cell carrying the antigen

Question 37

Explain why antibodies are only effective against a specific pathogen. (2 marks)

Answer 37

1) their binding sites are complimentary to the antigen | 2) they can bind to form an antigen-antibody complex

Question 38

Why might babies already have measles antibodies before their MMR vaccination? (application)

Answer 38

They have received maternal antibodies from their mother