Discovery & development of drugs

Chickenpox is an infectious disease that affects young children.

One symptom of chickenpox is small blisters on the skin.

Suggest one way chickenpox spreads from an infected person to other people.

Chickenpox is caused by a type of pathogen that cannot be treated with antibiotics.

Give the reason why chickenpox cannot be treated with antibiotics.

A vaccine that could be used to protect against chickenpox has been produced.

What does a vaccine contain that causes a person to become immune to a disease?

Give three reasons why a new vaccine must be tested.

Explain how a vaccine for chickenpox gives immunity against the disease.

You should refer to how the body responds to:

• the vaccine

• chickenpox pathogens that enter the body after vaccination.

Chickenpox is an infectious disease that affects young children.

One symptom of chickenpox is small blisters on the skin.

Suggest one way chickenpox spreads from an infected person to other people.

Chickenpox is caused by a type of pathogen that cannot be treated with antibiotics.

Give the reason why chickenpox cannot be treated with antibiotics.

A vaccine that could be used to protect against chickenpox has been produced.

What does a vaccine contain that causes a person to become immune to a disease?

Give three reasons why a new vaccine must be tested.

Explain how a vaccine for chickenpox gives immunity against the disease.

You should refer to how the body responds to:

• the vaccine

• chickenpox pathogens that enter the body after vaccination.

This question is about communicable diseases.

Measles is a communicable disease caused by a pathogen.

What type of microorganism causes measles?

Vaccinations help reduce the spread of measles.

Suggest two ways the spread of measles can be reduced.

Do not refer to vaccination in your answer.

Describe how the measles vaccine helps a person to become immune to the measles pathogen.

Norovirus is a type of virus.

Explain how viruses cause illness.

Drugs can help to reduce the symptoms of the norovirus infection.

New drugs must go through clinical trials before being licensed for use.

Give three reasons why clinical trials are needed.

Bacteria can cause a variety of diseases in humans.

What are two similarities between a bacterial cell and an animal cell?

Tick (✓) two boxes.

Salmonella food poisoning is caused by bacteria in food.

Give one symptom of salmonella food poisoning.

Do not refer to vomiting or diarrhoea in your answer.

What is the name of the first antibiotic developed?

A child with a severe bacterial infection was given a course of antibiotics.

Figure 7 shows how the concentration of live bacteria in the child’s body changed when taking the course of antibiotics.

The concentration of live bacteria in the body continued to increase after starting the course of antibiotics.

Suggest one reason why.

After 3 days of taking the antibiotic:

• the child felt better

• there were still bacteria in the child’s body.

Why did the child feel better?

Tick (✓) one box.

Suggest why doctors do not give antibiotics to patients with minor infections.

Figure 8 shows blood viewed using a microscope.

A vaccine will stimulate the production of antibodies.

Which part of the blood in Figure 8 produces antibodies?

Tick (✓) one box.

Which part of the blood in Figure 8 starts the clotting process?

Tick (✓) one box.

Bacteria can cause a variety of diseases in humans.

What are two similarities between a bacterial cell and an animal cell? Tick (✓) two boxes.

Salmonella food poisoning is caused by bacteria in food. Give one symptom of salmonella food poisoning. Do not refer to vomiting or diarrhoea in your answer.

What is the name of the first antibiotic developed?

A child with a severe bacterial infection was given a course of antibiotics.

Figure 1 shows how the concentration of live bacteria in the child’s body changed when taking the course of antibiotics.

The concentration of live bacteria in the body continued to increase after starting the course of antibiotics. Suggest one reason why.

After 3 days of taking the antibiotic:

• the child felt better

• there were still bacteria in the child’s body.

Why did the child feel better? Tick (✓) one box.

Suggest why doctors do not give antibiotics to patients with minor infections.

Figure 2 shows blood viewed using a microscope.

A vaccine will stimulate the production of antibodies. Which part of the blood in Figure 2 produces antibodies? Tick (✓) one box.

Which part of the blood in Figure 2 starts the clotting process? Tick (✓) one box.

New drugs are tested before they can be licensed for use with patients. Figure 2 shows how much time the different stages of testing took for one new drug.

Preclinical testing is done in a laboratory. What is the drug tested on in a laboratory? Give one example.

How many years did the clinical trials take for the drug in Figure 2 ?

During Phase 1 clinical trials, the drug is tested on healthy volunteers using low doses. What is the main purpose of Phase 1 testing? Tick (✓) one box.

During clinical trials, half of the patients are given a placebo in a double blind trial.

What is a placebo?

Who knows which patients are given the placebo and which patients are given the drug in a double blind trial? Tick (✓) one box.

Paracetamol and ibuprofen are two medicines used to reduce a high

body temperature. Doctors investigated which medicine was more effective at reducing high body temperature in 200 children who were ill. The children were put into two groups, which were matched for:

• age

• gender

• body mass.

Each group had 100 children. This is the method used.

1. Measure the body temperature of each child before any medicine is given.

2. Give children in Group 1 paracetamol.

3. Give children in Group 2 ibuprofen.

4. Measure the body temperature of each child every hour after the medicine is given.

Give two control variables in this investigation.

None of the children was given a placebo. Suggest one reason why.

Figure 3 shows the results.

What was the mean body temperature after 6 hours for the children given ibuprofen?

The doctors concluded that children with a high body temperature should be given ibuprofen and not paracetamol. Give two reasons for the doctors’ conclusion. Use Figure 3.

New drugs are tested and trialled before they can be licensed to treat patients. Figure 6 shows how much time the different stages of testing took for one new drug.

How much more time did the clinical trials take compared with the preclinical testing? Tick (✓) one box.

During Phase 1 clinical trials low doses of the drug are tested on healthy volunteers.

Suggest one reason why low doses of the drug are used in Phase 1 clinical trials.

Suggest two reasons why healthy volunteers are used in Phase 1 clinical trials.

The results of clinical trials can only be published after peer review by other scientists. Suggest one reason why the results must be reviewed by other scientists.

A drug is only licensed for the medical conditions it was tested to treat in the clinical trials. Drug regulations:

• control what drugs a doctor can prescribe

• ensure doctors can prescribe a drug with confidence

• protect patients.

AMD is an eye condition that can result in very poor vision. Doctors treat approximately 40 000 new cases of AMD each year. Two drugs licensed to treat AMD in the UK are drug A and drug B. In many other countries drug C is used to treat AMD. Drug C is only licensed in the UK to treat cancer. The cost per injection for each drug is:

• drug A £561

• drug B £800

• drug C £28

The number of injections required to treat AMD is the same for each drug.

In 2018 the High Court in the UK gave permission for drug C to be used to treat AMD. Evaluate the decision to allow the use of drug C to treat AMD in the UK.

Figure 10 shows a human heart.

Which blood vessel carries deoxygenated blood away from the heart to the lungs?

Tick (✓) one box.

The natural resting heart rate is controlled by a group of cells that act as a pacemaker.

Where in the heart are ‘pacemaker cells’ found?

Tick (✓) one box.

Some people may be treated with a drug to slow their heart rate.

Digitalis is a drug that slows the heart rate.

Where does the drug digitalis originate from?

Tick (✓) one box.

Beta blockers are another type of drug that slows the heart rate.

Table 2 shows information for people who do not take beta blockers and for people who do take beta blockers.

• Stroke volume is the volume of blood pumped out of the heart each time it beats.

• Cardiac output is the total volume of blood pumped out of the heart each minute.

Calculate stroke volume X in Table 2.

Use the equation: cardiac output = stroke volume × heart rate

Give your answer to 2 significant figures.

Some people who take beta blockers get out of breath when they exercise.

Explain why beta blockers can have this effect during exercise.

You should refer to information given in Table 2.

Figure 1 shows a human heart.

Which blood vessel carries deoxygenated blood away from the heart to the lungs? Tick (✓) one box.

The natural resting heart rate is controlled by a group of cells that act as a pacemaker. Where in the heart are ‘pacemaker cells’ found?

Tick (✓) one box.

Some people may be treated with a drug to slow their heart rate.

Digitalis is a drug that slows the heart rate. Where does the drug digitalis originate from?

Tick (✓) one box.

Beta blockers are another type of drug that slows the heart rate. Table 1 shows information for people who do not take beta blockers and for people who do take beta blockers.

• Stroke volume is the volume of blood pumped out of the heart each time it beats.

• Cardiac output is the total volume of blood pumped out of the heart each minute.

Calculate stroke volume X in Table 1. Use the equation: cardiac output = stroke volume × heart rate Give your answer to 2 significant figures.

Some people who take beta blockers get out of breath when they exercise. Explain why beta blockers can have this effect during exercise. You should refer to information given in Table 1.