Immunity

Question 1

when is a person immune to a disease?

Answer 1

when there is a reservoir of memory cells in their body

Question 2

what are memory cells a type of?

Answer 2

lymphocyte

Question 3

what do lymphocytes do when a person is infected with a pathogen?

Answer 3

make antibodies

Question 4

what type of antibodies do lymphocytes make?

Answer 4

antibodies that are specific to the antigens for that pathogen

Question 5

what happens when the pathogens are destroyed ?

Answer 5

some lymphocytes remain that can recognise that pathogen - these are memory cells.

Question 6

what is the function of memory cells?

Answer 6

If a pathogen infects a person for the second time the memory cells are ready for a rapid response so antibodies are made faster and in a larger quantity - the pathogen is killed before it can make somebody ill.

Question 7

what is another name for vaccination?

Answer 7

immunisation

Question 8

what is a vaccination?

Answer 8

A vaccine contains antigens from the pathogen. This triggers an immune response and the production of memory cells

Question 9

what do vaccines contain?

Answer 9

• live viruses or bacteria made harmless
• dead bacteria
• parts of a virus such as a protein coat which has the antigens on it
• modified toxins

Question 10

when are harmless live viruses or bacteria used in vaccines?

Answer 10

for TB or rubella

Question 11

when are dead bacteria used on vaccines?

Answer 11

for whooping cough

Question 12

when are parts of a virus used in vaccines?

Answer 12

for flu and hepatitus

Question 13

when are modified toxins used in vaccines?

Answer 13

for tetanus

Question 14

how does penicillin kill bacteria?

Answer 14

stops them making their cell walls.