4.1 Immunity

Question 1

define immunity

Answer 1

the ability to destroy a pathogen before it can harm the body

Question 2

what is the secondary immune response?

Answer 2

there are B and T memory cells circulating tin the blood which can recognize the specific antigen and the immunes system kicks in faster so production of antibodies starts sooner and is much more rapid so there is a higher concentration of antibodies than in the primary immune response

Question 3

what are the 4 types of immunity?

Answer 3

1. natural active immunity
2. artificial active immunity
3. natural passive immunity
4. artificial passive immunity

Question 4

natural active immunity

Answer 4

catching a disease and your own B cells are making the antibodies eg. you can get it from the cold

Question 5

artificial active immunity

Answer 5

a vaccination, weak pathogens are injected which activates the immune system so you make your own antibodies

Question 6

natural passive immunity

Answer 6

antibodies provided via the placenta or breast milk which make the baby immune to disease which is useful when the baby’s immune system is only just developing

Question 7

artificial passive immunity

Answer 7

injection of antibodies made by another individual eg done for tetanus

Question 8

what happens when you are vaccinated?

Answer 8

the deliberate exposure to the antigenic material means lymphocytes treats it as a real disease so immune system is activated and manufactures antibodies and memory cells
memory cells provide long term immunity

Question 9

why is a booster dose of a vaccination given?

Answer 9

makes body go through secondary immune response to raise antibody levels

Question 10

forms of vaccinations

Answer 10

• inactivated form of the pathogen
• a less harmful form of the pathogen
• isolated antigens from the pathogen

Question 11

how are epidemics being controlled?

Answer 11

health authorities have vaccination programmes to immunize all those over 65 and those at risk
vaccinations can be given via nasal spray
worldwide research is done to predict which strains of flu are most likely to spread in a given year

Question 12

what is herd immunity?

Answer 12

enough people are immune so the disease can no longer spread through the population

Question 13

what is ring vaccination?

Answer 13

vaccinating all the people in the immediate vicinity of the new case of the disease
also used in some parts of the world to control the spread of livestock disease