4.1.1: Communicable Diseases: Cell Recognition

Question 1

What is the purpose of proteins on the surface of cells?

Answer 1

To allow recognition by lymphocytes

Cells are labelled with unique shape proteins to distinguish between ‘self’ and ‘non-self’ cells.

Question 2

How do lymphocytes recognize ‘self’ cells?

Answer 2

By unique shape proteins on body cells

This mechanism prevents lymphocytes from attacking the body’s own cells.

Question 3

What happens when lymphocytes detect ‘non-self’ proteins?

Answer 3

They recognize them as foreign and destroy them

‘Non-self’ proteins can include abnormal body cells, toxins, pathogens, and cells from other organisms.

Question 4

What is an antigen?

Answer 4

A protein molecule on the surface of non-self cells

Antigens trigger an immune response and the production of antibodies.

Question 5

What triggers an immune response?

Answer 5

The presence of antigens

Antigens are typically found on the cell-surface of non-self cells.

Question 6

Fill in the blank: An antigen is typically a _______ molecule on the cell-surface of a membrane of non-self-cells.

Answer 6

[protein]

Question 7

True or False: Lymphocytes can attack ‘self’ cells if they recognize them incorrectly.

Answer 7

True

This can lead to autoimmune diseases where the body attacks its own cells.