Recognising non-self cells

Question 1

what are self cells?

Answer 1

Cells that are our own

Question 2

what are non-self cells?

Answer 2

Cells that are not our own.

Question 3

What is an immune response?

Answer 3

Our bodies ability to get rid of a Non-self cell.

Question 4

What are our two main types of White blood cells ( WBC)?

Answer 4

Lymphocites and Phagocytes.

Question 5

What are the 4 main threats that lymphocites can identify?

Answer 5

Pathogens, Toxins, cells from other humans, abnormal body cells

Question 6

What is an antigen?

Answer 6

An antigen is a protein in the cell surface membrane, which triggers an immune response.

Question 7

explain how a lymphocite recognises an antigen.

Answer 7

Lymphocites have receptors that are complemementary to the antigen.
the receptor and the antigen bind together, in order to form a specific immune response.

Question 8

Explain how a phagocyte recognises a non-self cell.

Answer 8

On the surface of all pathogens, there is a specific pattern of molecules.
Phagocytes have receptors which are complementary to the molecular patterns.
They then bind to the pathogen, thus triggering a non-sepcific immune response.

Question 9

Explain the whole process of Phagocytosis.

Answer 9

1. pathogen releases chemicals, which attract the pagocyte towards them.
2. the phagocyte begins to move towards the pathogen, along a concentration gradient.
3. The phagocytes receptors, then bind to the pathogen.
4. the phagocyte then engulfs the pathogen, encasing it in a vesicle, which we call a phagosome.
5. lyosomes then fuse with the phagosome. These lyosomes release enzymes, which then hydrolise the pathogen.
6. the soluble products are absorbed by the cytoplasm, and everything else is expelled from the phagocyte.