Antigens and antibodies

Question 1

Define antigen

Answer 1

It is a foreign molecule that stimulates the production of antibodies

Question 2

Define antibody

Answer 2

It is a protein produced by white blood cells (lymphocytes) in response to a specific antigen

Question 3

What do antigens include?

Answer 3

Antigens include molecules from the coats of viruses and the cell walls of bacteria, fungi and other micro-organisms.

Question 4

Where can antigens be found other than micro-organisms?

Answer 4

on foreign cells such as pollen grains, incompatible blood transfusions, transplanted tissues or organs and cancer cells.

Question 5

Is the antigen-antibody reaction highly specific or not?

Answer 5

It is a highly specific reaction

Question 6

What does it mean that the antigen-antibody reaction is highly specific?

Answer 6

There is a precise fit between the antigen and the antibody.
Each antibody is complementary to a single antigen.
Each antigen stimulates the production of only one specific antibody.

Question 7

What do antibodies and antigens do together?

Answer 7

Antibodies bind to antigens and allow the pathogens to be destroyed by lymphocytes.

Question 8

Antibodies trigger the complement system, which results in what?

Answer 8

which results in the pathogenic cells being burst