Chapter 7 Set 3

Question 1

What is active immunity? What are some examples?

Answer 1

When exposure to antigen causes the body to actively produce immunity.

This includes:
- The sensitisation of lymphocytes, producing cell mediated and antibody mediated immunity.
- Memory cells

Question 2

What is passive immunity?

Answer 2

When the body gets ‘ready-made’ antibodies from another source and does not need to actively work to produce the antibody rather the body is not exposed to the antigen so active immunity cannot develop.

This includes:
- Antibody received and neutralises any pathogens present but the antibodies will be used up.
- No memory cells are produced

Question 3

What is natural immunity?

Answer 3

Immunity that develops via natural processes in the human body.

Question 4

What is artificial immunity?

Answer 4

Scientific processes are used to create immunity.

Question 5

What is an example of active natural immunity? Describe the process of this example

Answer 5

E.g. The natural occurrence of measles.

If someone is exposed to the Measles virus, their immune system responds actively.
B-cells and T-cells (lymphocytes) become sensitised
produce antibodies to fight the virus via Antibody Mediated (Humoral) Immunity
Produce memory cells specific to the virus so the next encounter will be neutralised before symptoms develop.

Question 6

What is an example of active artificial immunity?

Answer 6

E.g. Recieving the vaccine for measles

A vaccine is given, containing either killed measles virus, substances that mimic the measles antigen, or a very mild form of the virus.
The body then responds actively to produce long lasting immunity.
- B-cells become sensitised
- Antibody produced via antibody-mediated immunity
- Memory cells produced
- Immunity to measles results.

Question 7

What is an example of passive natural immunity?

Answer 7

E.g. A child gets antibodies via breastfeeding or across placenta.

The antibodies are made naturally by the mother’s immune system.
Baby gets antibodies from breastmilk or across placenta.
The baby gets the antibody without the baby’s immune system having to do anything. The process is passive.
Baby then has circulating antibody to neutralise specific pathogen.
Doesn’t last – no active response from baby’s immune system, no memory-cells produced.

Question 8

What is an example of passive artificial immunity?

Answer 8

E.g. administration of snakebite antivenom

Antibodies to snake venom produced via a man-made process (artificial)
Antibody injected into patient’s bloodstream:
Antibody neutralises venom
Body does not work to develop immunity – gets antibody passively
Short term only – no memory-cells produced