Immune System

Question 1

What is the innate response

Answer 1

Non-specific mechanisms that protect the body e.g. skin, goblet cells, ciliated epithelial cells.

Question 2

What is the movement of cells / organisms in response to concentration gradient of certain chemicals called?

Answer 2

Chemotaxis

Question 3

What is an antigen?

Answer 3

proteins on the surface of ** foreign or abnormal** cells that trigger an immune response

Question 4

What’s the difference between lymphocytes and phagocytes

Answer 4

Lymphocytes are specific to complementary antigens where as phagocytes are not specific

Question 5

What is apoptosis

Answer 5

Programmed cell death

Question 6

What is the process of phagocytosis (7)

Answer 6

1. Phagocytes move to pathogen by chemotaxis
2. Pathogen attaches to receptors on the surface membrane of a pathogen
3. Phagocyte engulfs pathogen by phagocytosis
4. Membrane pinches around pathogen to form phagosome
5. Lysosome forms with phagosome to hydrolyse pathogen
6. Digested contents are released into the cytoplasm of the cell by exocytosis.
   -7- some APC’s then present fragments of the antigen on their plasma membrane to recruit lymphocytes.

Question 7

What are the two types of t-cell ?

Answer 7

Cytotoxic T cell
T helper cell

Question 8

What type of immunity are T cells part of?

Answer 8

Mediated immunity

Question 9

Where are T cells:
made
Matured
Stored

Answer 9

Made - bone marrow
Matured- in the Thymus gland
Stored- Lymph nodes

Question 10

What activates a T helper cell ? As part of what process?

Answer 10

an APC- Antigen Presenting Cell
As part of clonal expansion

Question 11

After a cell is activated, it divides rapidly, what’s this called?

Answer 11

Clonal expansion

Question 12

Helper T cells release cytokines that…
1. __________
2. __________
3. __________
4. __________

Answer 12

1. Activates b-cells to proliferate to become B - memory cells
2. Activates be cells to proliferate to become plasma cells
3. Activate Cytotoxic T-cells
4. Increases the rate of phagocytosis

Question 13

What do cytotoxic T-cells do?

Answer 13

Attach to antigens on pathogens
Secrete toxins to kill infected cells and pathogens - by punching holes in the surface membrane.
(Kill infected cells so that viruses can’t replicate)

Question 14

What is humoral response?

Answer 14

An immune response leas by macromolecules e.g. antibodies

Question 15

Where are B-cells produced and matured?

Answer 15

Bone marrow