5.3- Cell Mediated immunity

Question 1

What is an antigen?

Answer 1

Any part of an organism or substance that is recognised as non-self by the immune system and stimulate a response.

Question 2

Do specific immune responses create short or long term immunity?

Answer 2

Long- term

Question 3

Where are lymphocytes produced?

Answer 3

By stem cells in the bone marrow

Question 4

What are the two types of lymphocytes?

Answer 4

B-Lymphocytes (Hurmoral) and T- Lymphocytes (Cell-mediated)

Question 5

What type of foreign material does T-Lymphocytes respond too?

Answer 5

Self-cells that have been affected (Virus) or cells from other individuals (Not genetically the same).

Question 6

How do the T-lymphocytes know that a phagocyte has engulfed a pathogen?

Answer 6

The phagocyte will display some of the pathogens foreign material on the cell surface membrane.

Question 7

How do the T-lymphocytes know that a virus has invaded a self-cell?

Answer 7

They present viral antigens on the cell-surface membrane.

Question 8

How do T-lymphocytes know that transplanted or cancer cells are present?

Answer 8

They both have antigens presented on the outer cell-surface membrane.

Question 9

What is the cell-mediated immunity?

Answer 9

Where T-lymphocytes respond to antigens that are presented on a body cell- Not in the bloodstream or bodily fluid.

Question 10

What are the 4 things that, after mitosis, the T helper cell can do?

Answer 10

1) Develop into memory cells which allow a rapid response to future infections.
2) Stimulate phagocytosis to engulf pathogens.
3) Stimulate B cells to divide and secrete antibodies.
4) Activate Cytotoxic T cells.

Question 11

What is the first step in the cell- mediated response?

Answer 11

The phagocyte has engulfed the pathogen and is now presenting antigens on its cell surface membrane.

Question 12

What happens after the phagocyte presents the foreign antigens? Step 2 in CMR

Answer 12

The T helper cells have receptors that are complementary to the antigens being presented, then one of the four responses is produced.

Question 13

How do cytotoxic T cells help to destroy pathogens? CMR

Answer 13

They produce a protein called perforin that creates pores within the cell-surface membrane, allowing substances to enter the cell and the cell dies.

Question 14

What do B cells do?

Answer 14

They produce antibodies that are complementary to the pathogens cell-surface material.

Question 15

What happens after the B cell binds with the foreign antigen presented on the cell-surface membrane? HR

Answer 15

The antigen enters the B cell by endocytosis and then gets processed and presented on its cell surface membrane.

Question 16

What happens after the antigen has been processed and is presented on the cell surface membrane? HR

Answer 16

T helper cells will bind to the processed antigens and stimulate the B cells to divide by mitosis.

Question 17

What is clonal selection?

Answer 17

Where certain B lymphocytes are cloned and all produce the same type of antibodies.

Question 18

What are the two types of cells that the cloned B cells can turn into?

Answer 18

Plasma cells (Secrete antibodies into the blood plasma) and memory cells (circulate the blood and tissue fluid).

Question 19

What is the primary immune response within the humoral response?

Answer 19

The cloned cells that mature into plasma cells.

Question 20

What is the secondary immune response within the humoral response?

Answer 20

The cloned cells that mature into memory cells.