VACCINATION

Question 1

How do vaccines prevent illness in an individual?

Answer 1

-Vaccines introduce small quantities of dead or inactive forms of a pathogen into the body

-white blood cells respond and stimulated to produce antibodies specific to pathogen complementary to the antigens on the pathogens

-if the same pathogen re-enters the body (reinfection) white blood cells release antibodies, with the antibodies being release at a faster rate in larger quantities

-the antibodies destroy + kill the pathogen preventing infection and preventing any symptoms OR antibodies cause pathogens to clump together

-WBCs engulf pathogens by phagocytosis

Question 2

How can vaccines prevent the spread of pathogens?

Answer 2

by immunising a large proportion of the population, the spread of the pathogen is reduced as there are less people to catch the disease from (herd immunity)

Question 3

Advantages of vaccination:

Answer 3

-have eradicated many diseases so far e.g. small box and reduced the occurrence of many e.g. rubella

-epidemics (lots of cases in an area) can be prevented through herd immunity

Question 4

Disadvantages of vaccination:

Answer 4

-not always effective in providing immunity

-bad reactions (e.g. fevers) can occur in response to vaccines (although very rare)

Question 5

what are antigens

Answer 5

Antigens are substances, often proteins, found on the surface of cells, including those of pathogens like bacteria and viruses, that trigger an immune response

Question 6

memory cells

Answer 6

-remember the specific antibody used to fight specific pathogen

-so when you body come in contact with the same pathogen

-these memory cells can make antibodies quickly before you get sick