Infection and Response

Question 1

what are pathogens?

Answer 1

micro organisms that cause infectious disease.

Question 2

bacteria, viruses, fungi or protists =

Answer 2

types of pathogens.

Question 3

Viral diseases =

Answer 3

• may reproduce rapidly.
• live and reproduce inside cells causing damage.

Question 4

Bacterial diseases =

Answer 4

• may reproduce rapidly.
• may produce toxins that damage tissues and make us feel ill.

Question 5

Pathogens may infect plants or animals and can be
spread by ….

Answer 5

direct contact , by water or by air

Question 6

What do pathogens need from the host organism?

Answer 6

Suitable conditions and nutrition to be able to grow and reproduce.

Question 7

Malaria ——–>

Answer 7

symptom = Recurrent fever
transmission = By a vector from an infected person.
control the spread by = Preventing breeding of mosquitoes or use of a net to prevent being bitten.
caused by = Protist.

Question 8

Tobacco Mosaic Virus ——–>

Answer 8

symptom = Mosaic pattern on leaves.
transmission = Enters via wounds in epidermis caused by pests.
control spread by = Remove infected leaves and control pests which are damaging leaves.
caused by = Virus

Question 9

Measles ——–>

Answer 9

symptom = Fever, Red skin rash.
transmission = Droplet infection from sneezes and coughs.
control spread by = Child Vaccination.
caused by = Virus.

Question 10

Gonorrhoea ———>

Answer 10

symptoms = Green discharge from penis or vagina.
transmission = Direct sexual contact or body fluids.
control spread by = Use of a condom and treat infected person with antibiotics.
caused by = Bacteria

Question 11

Rose Black Spot ——–>

Answer 11

symptoms = Purple black spots on leaves.
transmission = Spores carried via wind or water.
control spread by = Remove infected leaves and spray with pesticide.
caused by = Fungus.

Question 12

Salmonella ———>

Answer 12

symptoms = Fever, cramp, vomiting, diarrhoea.
transmission = Food prepared in unhygienic conditions or not cooked properly.
control spread by = Improve food hygiene, wash hands, vaccinate poultry, cook food thoroughly.
caused by = Bacteria.

Question 13

phagocytosis =

Answer 13

White blood cells engulf the pathogens and digest them.

Question 14

lymphocytes =

Answer 14

White blood cells identify the antigen on the pathogen. They make specific antibodies to destroy the pathogens. If a person is infected again by the same pathogen, the white blood cells make the antibodies much faster.

Question 15

Bacteria may produce toxin =

Answer 15

White blood cells release specific antitoxins to neutralise the effect of the toxin.

Question 16

What is an antigen?

Answer 16

A protein on the surface of a pathogen

Question 17

Why will the antibody produced for measles not be effective in other diseases?

Answer 17

Antibody has a specific shape which fits with a specific
antigen.

Question 18

Why are dead or inactive pathogens used in a vaccine?

Answer 18

To stimulate white blood cells to make antibodies without causing the disease.

Question 19

What happens if the live pathogen invades the body after being vaccinated?

Answer 19

White blood cells able to respond much faster and produce more antibodies quicker to destroy the pathogens so the person doesn’t suffer the symptoms of the disease.

Question 20

What is an antibiotic and what is it used for?

Answer 20

Kills bacteria inside the body without harming human cells.

Question 21

Why is there a growing concern about bacterial resistance to antibiotics?

Answer 21

the resistant bacteria are not killed and can continue to
multiply inside the body making the person very ill and infecting others too.

Question 22

Painkillers are used to treat the symptoms of a disease but do not ….

Answer 22

kill the pathogens.

Question 23

Aspirin is a painkiller and anti-inflammatory drug.
This was first found in ….

Answer 23

willow bark.

Question 24

Foxglove plants have been a source of the drug digitalis which acts on the ….

Answer 24

heart.

Question 25

Penicillin is an antibiotic drug. It originates from ….

Answer 25

mould.

Question 26

Efficacy =

Answer 26

how effective the drug is.

Question 27

Toxicity =

Answer 27

how poisonous the drug is.

Question 28

Optimum dose =

Answer 28

minimum amount of the drug which provides the best response.

Question 29

put them in order:
Drugs are trialled on live animals.
Drugs are trialled on people with the disease the drug is for.
Drugs are trialled in laboratories on cells and tissue cultures.
Drugs are trialled on healthy volunteers.

Answer 29

2. Drugs are trialled on live animals.
3. Drugs are trialled on people with the disease the drug is for.
4. Drugs are trialled in laboratories on cells and tissue cultures.
5. Drugs are trialled on healthy volunteers.

Question 30

What is a placebo?

Answer 30

A medicine that does not contain the drug that is being trialled.

Question 31

Why is it used?

Answer 31

A placebo is used to check that there are no other factors which may cause the patient‘s condition to improve without the drug.

Question 32

Name 3 ways you can detect that a plant is diseased.

Answer 32

leaf spots/discolouration, growths, malformed stems or leaves, presence of pests, stunted growth, areas of decay.

Question 33

What is chlorosis and how can it be prevented?

Answer 33

Chlorosis is the yellowing of the leaves. It can be prevented by providing the plant with magnesium.