biology - communicable and non-communicable diseases

Question 1

Q1.a. Define Communicable Disease.

1 mark

Answer 1

a disease that can be spread from one person to another.

Question 2

Q1.b. A woman becomes ill and has the following symptoms:
- pain when urinating
- thick yellow discharge from vagina.
Which communicable disease does the woman have?
(1 mark).

Answer 2

gonorrhoea.

Question 3

Q1.c. Tuberculosis is a bacterial infection that affects the lungs.
Tuberculosis causes severe discomfort.
What type of medicine should be used to kill the tuberculosis bacteria?
(1 mark).

Answer 3

antibiotics.

Question 4

Q1.d. What type of medicine should be used to treat the symptoms of TB?
(1 mark).

Answer 4

painkillers.

[𝙖𝙡𝙡𝙤𝙬 𝙖𝙨𝙥𝙞𝙧𝙞𝙣, 𝙥𝙖𝙧𝙖𝙘𝙚𝙩𝙖𝙢𝙤𝙡, 𝙞𝙗𝙪𝙥𝙧𝙤𝙛𝙚𝙣 𝙖𝙣𝙙 𝙤𝙩𝙝𝙚𝙧 𝙘𝙤𝙧𝙧𝙚𝙘𝙩 𝙗𝙧𝙖𝙣𝙙 𝙣𝙖𝙢𝙚𝙨.]

Question 5

Q1.e. Describe the ways in which the human body defends itself against the tuberculosis bacterium.
(4 marks).

Answer 5

1) skin stops the bacterium entering the body.
2) blood cots to stop bacteria entering.
- 3) stomach acid will kill the bacterium if it is in food.
- 4) nose have mucus to trap the bacteria.
- 5) nose have cilia/hair to move mucus out.
- 6) white blood cells destroy the bacteria if infected.
7) by phagocytosis.
8) by antibodies.
9) bu antitoxins.

Question 6

Q2.a. In 2014 there was an outbreak of Ebola virus disease (EVD) in Africa.
At the time of the outbreak there were:
- no drugs to treat the disease
- no vaccines to prevent infection
By March 2015 there were an estimated 9850 deaths worldwide from EVD.
The number of deaths is an estimate.
Suggest why it is an estimate rather than an exact number.
(1 mark).

Answer 6

any 𝗼𝗻𝗲 from:

• not all deaths recorded.
• not all causes of deaths recorded.

Question 7

Q2.b. Why were no antibiotics used to treat EVD?

1 mark

Answer 7

antibiotics only kill bacteria.

Question 8

Q2.c. After the outbreak began, drug companies started to develop drugs and vaccines for EVD.
A drug has to be thoroughly tested ad trialled before it is licensed for use.
Testing, trialling and licensing new drugs usually takes several years.
Define each word:
DOSE
EFFICACY
TOXICITY
(2 marks).

Answer 8

DOSE - the concentration of the drug to be used and how often the drug should be given.
EFFICACY - whether the drug works to treat the illness.
TOXICITY - side effects making the person ill.

Question 9

Q2.d. The results of drug testing and drug trials are studied in detail by other scientists.
Only then can the results be published by the drug company.
Suggest one reason why the results are studied by other scientists.
(1 mark).

Answer 9

any 𝗼𝗻𝗲 from:

• to prevent false claims.
• to make sure the conclusions are correct/valid.
• to avoid bias.

Question 10

Q3.a. Coronary heart disease (CHD) is a non-communicable disease.
CHD is caused when fatty material builds up in coronary arteries.
Explain what non-communicable disease is.
(2 marks).

Answer 10

A disease that is not caused by microorganism therefore it is not spread from a person to another.

Question 11

Q3.b. The diagram below shows a coronary artery of someone with CHD.
Explain how CHD can cause a heart attack.
(3 marks).

Answer 11

CHD can stop blood from flowing so no oxygen can reach the heart therefore it can’t release the energy needed.

Question 12

Q3.c. Explain how lifestyle and medical risk factors increase the chance of developing CHD.
(4 marks).

Answer 12

Obesity can increase your chance of getting CHD as you can get diabetes from it there leading to too much fat.
Alcohol can also be a risk factor that would increase you chances of developing CHD as it rises your cholesterol levels.
The way you eat/diet can also be a risk factor as it can lead to obesity which also leads to other risk factors and can increase you chances of diabetes and high cholesterol levels.

Question 13

Q4.a. Bacteria and viruses can reproduce quickly inside the body and make us feel ill. These organisms may cause symptoms such as a high body temperature.
How do bacteria and viruses make us feel ill?
(1 mark).

Answer 13

They produce toxins.
[𝙖𝙡𝙡𝙤𝙬 𝙥𝙤𝙞𝙨𝙤𝙣𝙨
𝙖𝙡𝙡𝙤𝙬 𝙙𝙖𝙢𝙖𝙜𝙚 𝙗𝙤𝙙𝙮 𝙘𝙚𝙡𝙡𝙨].

Question 14

Q4.b.i. This investigation would have been improved if a fourth group of children had been included.
The children in each group were matched for age and gender.
Suggest one other factor the children should have been matched for to make this investigation valid.
(1 mark).

Answer 14

Body mass.
[𝙖𝙡𝙡𝙤𝙬 𝙬𝙚𝙞𝙜𝙝𝙩
𝙖𝙡𝙡𝙤𝙬 𝙚𝙩𝙝𝙣𝙞𝙘𝙞𝙩𝙮].

Question 15

Q4.b.ii. What would the children in the fourth group have been given?
(1 mark).

Answer 15

A placebo.

Question 16

Q4.b.iii. Suggest why this would have improved the investigation.
(1 mark).

Answer 16

any 𝗼𝗻𝗲 from:

• as a control group.
• for comparison.
• to see if the drugs worked.
• to take account of psychological effect.

Question 17

Q4.c.i. The children’s body temperatures were measured before any medicine was given and every hour after treatment started.
The mean body temperatures for each of the three groups are shown in the figure below.
What was the difference in mean body temperature after 4 hurt between the group taking paracetamol only and the group take ibuprofen only?

Answer 17

1.2

Question 18

Q4.d.i. How many hours did the mean body temperature stay normal or below normal, when taking both paracetamol and ibuprofen compared to taking ibuprofen only?

Answer 18

3 hours.

Question 19

Q4.d.ii. Giving only ibuprofen might be better than giving a combination of paracetamol and ibuprofen because….

Answer 19

there is lees of a chance of overdose/giving too much and the ibuprofen nearly works as fast as the paracetamol.

Question 20

Q5.a. The MMR vaccine is used to protect children against measles, mumps and rubella.
Explain, as fully as you can, how the MMR vaccine protects children from these diseases.

Answer 20

The vaccine helps with the production of antibodies as the pathogens are dead therefore when the disease reintroduces itself, the antibodies will quickly reproduce kill the pathogens.
It can also help produce antitoxins.

Question 21

Q5.b.i. (there will be a passage)
Use the information from the passage above to answer these questions.
Was Dr Wakefield’s report based on reliable scientific evidence?
Explain the reasons for your answer.

Answer 21

The conclusion was based solely on what the parent stated and the sample size was small with only 12 kids.

Question 22

Q5.b.ii. Might Dr Wakefield’s report have been biased?

Give the reason for your answer.

Answer 22

Yes

as the parents were paying him.