Immunology and Neurobiology Unit 3 KA 7

Question 1

What is Immunity?

Answer 1

Immunity is the ability of an organism to resist a particular infection or toxin by the action of specific antibodies

Question 2

What is Immunisation?

Answer 2

Immunisation is the process by which a person develops immunity to a disease-causing organism

Question 3

What does Naturally acquired active immunity refer to?

Answer 3

Naturally acquired active immunity refers to the protection gained when a person acquires active immunity by natural means - survived an infection so secondary response occurs

Question 4

What does Artificially acquired active immunity refer to?

Answer 4

Artificially acquired active immunity refers to the protection gained when a person receives a Vaccination, creating an immunological memory

Question 5

What are the four different types of Immunity?

Answer 5

1) Passive Natural
2) Active Natural
3) Passive Artificial
4) Active Artificial

Question 6

What is Passive Natural immunity?
Definition + (2) + Example

Answer 6

Another source of antibodies -
1) Provides immediate protection
2) Short term

e.g. Antibodies given across placenta from mother to baby

Question 7

What is Active Natural immunity?
Definition + (3) + Example

Answer 7

Body makes antibodies after exposure -
1) Protection develops after long time
2) Long lasting
3) Involves memory cells

e.g. Natural exposure to pathogen so body makes memory cells

Question 8

What is Passive Artificial immunity?
Definition + (3) + Example

Answer 8

Another source of antibodies is given -
1) Provides immediate protection
2) Short term
3) Requires medical treatment

e.g. Direct iinjection of tetanus (tetanus shot)

Question 9

What is Active Artificial immunity?
Definition + (4) + Example

Answer 9

Body makes antibodies after pathogen is given -
1) Protection develops after a long time
2) Long lasting
3) Involves memory cells
4) Requires medical treatment

e.g. Vaccination of MMR

Question 10

How can Immunity be developed by vaccinations?

Answer 10

Immunity can be developed by vaccinations by using antigens from infectious pathogens so that the body will create memory cells

Question 11

What Antigens may be used in vaccinations? (4)

Answer 11

1) Inactivated pathogen toxin
2) Dead pathogen
3) Parts of pathogens
4) Weakened pathogens

Question 12

How do Vaccinations work?

Answer 12

Vaccinations work by inducing a primary immune response and creating memory cells in an individual, but because the antigen in a vaccination is not fully functioning it will not cause disease symptoms

Question 13

What is an Adjuvant?

Answer 13

An Adjuvant is a chemical substance that is usually mixed with antigens when making a vaccination because it makes the vaccine more effective and enhances the immune response

Question 14

What is Herd Immunity?

Answer 14

Herd Immunity is when a large percentage of a population are immunised, reducing the chance that non-immune individuals will come in contact with infected individuals

Question 15

Why is Herd Immunity important?
(2)

Answer 15

1) Reduces the spread of diseases
2) Protects vulnerable and non-vaccinated individuals

Question 16

What is necessary for Herd Immunity to be effective?

Answer 16

For Herd Immunity to be effective, it is necessary that only a minority of the population is left unvaccinated

Question 17

What is the Herd Immunity Threshold?

Answer 17

The Herd Immunity Threshold is the percentage of immune individuals in a population above which a disease no longer manages to persist

Question 18

What does the Herd Immunity Threshold depend on? (3)

Answer 18

1) The type of disease
2) The effectiveness of the vaccine
3) The density of the population

Question 19

In most countries, what is the Public health policy for combating common diseases?

Answer 19

In most countries, the public health policy for combatting common diseases is to use mass vaccination programmes to create herd immunity

Question 20

Why is implementing widespread vaccinations not always possible? (2)

Answer 20

1) Poverty (developing countries)
2) Vaccination rejection (developed countries)

Question 21

What is Antigenic Variation?

Answer 21

Antigenic Variation is when pathogens change their antigens so they can avoid the effect of immunological memory, memory cells will not be effective against them