Immunity -Jamie-lee Gordon

Question 1

Natural immunity

Answer 1

• bodies first line of defence against pathogens that infiltrate the body
• the external barrier that prevents harmful substances from entering the body
• skin is the first line of defence in the human body

Question 2

Innate immunity

Answer 2

-physical, chemical and genetic barriers
eg.) skin
coughing
sneezing reflexes
tears
mucous

Question 3

Pathogens

Answer 3

-organisms that cause diseases

Question 4

Role of antigens

Answer 4

• are protein molecules

- occur as markers on the surface of all body cells, viruses, bacteria, protozoa and fungi

Question 5

Lymphocytes

Answer 5

-occur in the lymph glands, spleen and blood
-2 types
> B-lymphocytes
>T-lymphocytes
(they play the most important role in the in active immune response)

Question 6

B-lymphocytes

Answer 6

• have receptor proteins on their surface that attach to specific antigens, recognising them as foreign
• they multiply, producing millions of new B-lymphocytes
• the new B-lymphocytes produce antibodies that are released into the blood plasma