Vaccinations

Question 1

What is passive immunity?

Answer 1

• Antibodies introduced from outside source.
• No plasma/ memory cells made.
• No long-term immunity/ short-lived.

Question 2

Give 2 types and examples of passive immunity.

Answer 2

1.) Natural: individual given antibodies by another individual (rather than producing their own.) Ie. babies via placenta/ new borns via breast-milk.
2.) Artificial: antibodies are made and given to individual ie. antivenom

() - extra info for clarification.

Question 3

What is active immunity?

Answer 3

• Antibodies are produced by own inidividuals’ memory cells.
  -Long-lasting immunity because antibody produced in response to antigen.

Question 4

Give 2 types and examples of active immunity.

Answer 4

1.) Natural: individual is exposed to pathogen naturally - leading to memory cells/ antibodies being produced.
2.) Artificial: immunity stimulated by vaccination.
Both cases, memory cells are made.

Question 5

True or False

Vaccines can only be given to individual as an injection into the bloodstream.

Answer 5

• False.
• Vaccines can also be given as nasal spray/ taken through the mouth.

Question 6

What different things can a vaccine be composed of?

Answer 6

• Vaccine COULD BE:
• Foeign antigens of pathogen.
• Weakened/ dead pathogens.

Question 7

When person is given vaccine, it leads to production of antibodies against disease-causing organism. Explain how.

Answer 7

1.) Vaccine contains antigen from pathogen.
2.) . Macrophage presents antigen on its surface.
3.) T- helper cell with complementary receptor/ site protein binds to antigen;
4.) T helper cell stimulates B cell;
5.) With comp antibody on its surface.
6.) B cell divides by mitosis (clonal selection) - forming clones ALL secreting/ producing same antibody. Clones differentiate into plasma/ memory cells.
7.) B cell (specifically plasma cells)secretes large amount of antibodies rapidly.

Question 8

What lives longer in the bloostream, plasma cells OR memory B cells?

Answer 8

• Memory cells live longer. Plasma cells = short-lived.

Question 9

What happens on secondary exposure of pathogen after individual has already been exposed to the pathogen through vaccination?

Answer 9

• Memory cells are activated, will divide rapidly (by mitosis) into plasma cells if they collide with specific antigen.
• More antibodies are produced (by memory cells), more rapidly.
• Antibodies destroy pathogens.
• Memory cells will live/ remain in blood for longer.

Question 10

What is the concept of “herd immunity?”

Answer 10

• If enough of population are vaccinated, the pathogen cannot spread easily amongst the population.
• This reduces the spread (of the pathogen.)

() - extra info for clarification.

Question 11

Give 1 reason why is it virtually impossible to vaccinate EVERY INDIVIDUAL in a population?

MS answer

Answer 11

• Allergies

Question 12

What happens during primary immune response?

Answer 12

• Weakened/ dead pathogen OR antigens
• Will stimulate memory cells to be made.

Question 13

Ethical issue associated with vaccines

Answer 13

• They are tested on animals before given to humans, which some people see as cruel as animal cannot give consent.

Question 14

Why is passive immunity short-term, why is active immunity long-term?

Answer 14

• Passive immunity = short term: because antibody is broken down.
• Active immunity = long term: because antibody is produced in response to the antigen.