Defence Against Pathogens

Question 1

What may bacteria and viruses do

Answer 1

Reproduce rapidly inside the body and produce toxins which make us feel ill

Question 2

What do viruses do

Answer 2

Damage the cells in which they reproduce

Question 3

How do white blood cells help to defend against pathogens

Answer 3

Ingesting pathogens

Producing antibodies which destroy particular bacteria/viruses

Producing antitoxins, which counteract the toxins released by pathogens

Question 4

What does the immune system of the body do

Answer 4

Produces specific antibodies to kill a particular pathogen

Leading to immunity from that pathogen

Question 5

What happens in some cases

Answer 5

Dead or inactive pathogens stimulate antibody production

Question 6

What happens if a large population is immune to a pathogen

Answer 6

The spread of the pathogen is much reduced

Question 7

What did Semmelweiss do

Answer 7

Recognised importance of hand washing in the prevention of spreading some infectious diseases
Insisted doctors washed their hands before examine patients
REDUCED NUMBER OF DEATHS FROM INFECTIOUS DISEASES

Question 8

What do some medicines such as painkillers do?

Answer 8

Help to relieve the symptoms of infectious disease but don’t kill pathogens

Question 9

What are antibiotics

Answer 9

Medicines that help to cure bacterial disease by killing infectious bacteria inside the body

Question 10

What can antibiotics not be used to do

Answer 10

Kill viral pathogens which live and reproduce inside cells

Question 11

What should specific bacteria be treated by?

Answer 11

Specific antibiotics

Question 12

What has the use of antibiotics greatly reduced

Answer 12

Deaths from infectious bacterial diseases

Question 13

What has overuse and innapropiate use of antibiotics increased

Answer 13

The rate of development of antibiotic resistant strains of bacteria

Question 14

What does mutations of pathogens do

Answer 14

Produces new strains

Antibiotics and vaccinations may no longer be effective against a new resistant strain of the pathogen

Question 15

What will the new strain do

Answer 15

Spread rapidly because people are not immune to it and there’s no effective treatment

Question 16

What do antibiotics do

Answer 16

Kill individual pathogens of the non resistant strain

Question 17

What do individual resistant pathogens do

Answer 17

Survive and reproduce so the population of the resistant strain increases

Question 18

What are antibiotics used to treat nowadays

Answer 18

Non serious infections so the rate of development resistant strains is slowed down

Question 19

How can people be immunised against a disease

Answer 19

By introducing small quantities of dead or inactive forms of the pathogen into the body

Question 20

What do vaccines do

Answer 20

Stimulate the white blood cells to produce anti bodies that destroy the pathogens
Making the person immune to future infections by the microorganism

Question 21

What does the body do if the microorganism tries to infect again in the future

Answer 21

It can respond by rapidly making the correct antibody, in the same way as if the person had previously had the disease

Question 22

How do you grow micro organisms (agar culture)

Answer 22

1. Sterilise agar jelly and Petri dish to kill unwanted microorganisms
2. Put inoculating loop into Bunsen burner to sterilise
3. Lid of Petri dish should be secured with adhesive tape to prevent micro organisms from the air contaminating it

Question 23

What temp should cultures be incubated at

Answer 23

25 degrees reducing the likelihood of growth of pathogens that might be harmful to humans

Question 24

What is a pathogen

Answer 24

A micro organism which causes infectious disease