AQA GCSE Trilogy Biology Paper 1 Foundation November 2020 question paper 8464/B/1F

Being overweight can affect the health and life expectancy of a person.

What is one lifestyle change a person could make to help them lose body mass? Tick (✓) one box.

Exercise has many health benefits. Give two health benefits of regular exercise. Do not refer to losing body mass in your answer.

During exercise, breathing rate increases to provide more oxygen for aerobic respiration.

What is the equation for aerobic respiration? Tick (✓) one box.

Figure 1 shows the human breathing system.

Where does gas exchange take place? Tick (✓) one box.

A scientist investigated the effect of exercise on the breathing rate of four people. This is the method used.

1. Measure the resting breathing rate.

2. Exercise for 10 minutes.

3. Measure the breathing rate as soon as exercise stops.

4. Record the time taken for the breathing rate to return to the resting rate.

Table 1 shows the results.

The scientist concluded that person B was the fittest. Give two reasons that support the scientist’s conclusion. Use Table 1.

Suggest two reasons why the scientist’s conclusion may not be valid.

Give two changes that happen in the body during aerobic exercise. Do not refer to increased breathing rate in your answer.

Muscles respire anaerobically during vigorous exercise. Complete the sentences. Choose answers from the box.

Muscles respire anaerobically if they do not have

Anaerobic respiration of glucose produces.

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.

Water is lost from the leaves of plants through pores called stomata.

What is the loss of water from a leaf called? Tick (✓) one box.

Which cells control the size of stomata? Tick (✓) one box.

A student investigated the water loss when different surfaces of leaves were covered in grease. The grease blocks the stomata.

This is the method used.

1. Remove four similar leaves from one plant.

2. Put grease on different surfaces of the leaves as shown in Figure 4.

3. Record the mass of each leaf and attach the four leaves to a string.

4. After 24 hours record the mass of each leaf again.

Table 2 shows the results.

Calculate value X in Table 2.

The loss in mass of water was measured after 24 hours. Calculate the mass of water lost in grams per hour for leaf D.

The student concluded: ‘More water is lost from the lower surface of a leaf than from the upper surface.’

What evidence is there in Table 2 to support the student’s conclusion?

What do the results in Table 2 show about the number of stomata on the surfaces of a leaf? Tick (✓) one box.

The investigation was done at 20 °C How would the mass of water lost be different if the investigation was done at 25 °C? Give a reason for your answer.

Pathogens cause infectious diseases.

Draw one line from each disease to the type of pathogen that causes the disease.

The body defends itself against pathogens in different ways.

Give two ways that the body prevents pathogens entering the body.

If pathogens do enter the body the immune system tries to destroy the pathogens. Describe how the immune system defends the body against disease.

Give one reason why antibiotics cannot be used to treat HIV infections.

Give two ways to prevent the spread of HIV.

Some people with a HIV infection develop AIDS. Some people with AIDS may die from a different type of infection, such as a chest infection.

Why do people with AIDS die from a different type of infection? Tick (✓) one box.

A student investigated the effect of different concentrations of sugar solution on pieces of potato. This is the method used.

1. Cut five pieces of potato.

2. Record the starting mass of each piece of potato.

3. Place each piece of potato in a different concentration of sugar solution.

4. After 24 hours remove the pieces of potato from the solutions.

5. Record the final mass of each piece of potato.

6. Calculate the change in mass for each piece of potato.

What is the independent variable? Tick (✓) one box.

Table 3 shows the results.

Explain why the potato in 0.0 mol/dm³ sugar solution increased in mass.

Complete Figure 5. Some of the results have been plotted for you. You should:

• plot the data from Table 3

• draw a line of best fit through all the points.

The mass of a piece of potato does not change when: concentration of solution inside cells = concentration of solution outside cells

Determine the concentration of sugar solution inside the potato cells. Use Figure 5.

Table 3 is repeated below.

Calculate the percentage change in mass for the potato in 0.2 mol/dm³ sugar solution. Use Table 3. Use the equation:

Give your answer to 3 significant figures.

Starch is digested to form sugar molecules in the digestive system.

What is the name of the enzyme that digests starch?

Where are most food molecules absorbed? Tick (✓) one box.

Figure 6 shows two villi. Figure 6 also shows one cell on the surface of a villus as seen using an electron microscope.

Give one advantage of using an electron microscope compared with using a light microscope.

What type of blood vessel is labelled X ? Tick (✓) one box.

The real length of one villus is 0.8 mm Calculate the image length if the villus is viewed at a magnification of ×20 Use the equation:

Figure 7 shows two cells from the surface of a villus. There are sugar molecules inside and next to each cell.

Name the process by which sugar moves into cell A.

Name the process by which sugar moves into cell B.

Give one use of sugar in the body.

Figure 6 is repeated below.

Explain how villi are adapted for efficient absorption of sugar molecules.