1 of 5

The human body within

The immune system

Gabriele

2 of 5

Any substance capable of producing an immune response is known as an antigen.

3 of 5

The immune system

Three lines of defence

Skin and mucous membranes

Phagocytosis

antibodies

Phagocytes

B-lymphocytes

T-lymphocytes (cytotoxic, helper, suppressor)

Monocytes

Macrophages

Neutrophils

4 of 5

The cells of the immune system

5 of 5

Antibodies are secreted by lymphocytes B and they can match and counteract any antigen.