AQA GCSE Synergy Paper 2: Life and environmental sciences Higher November 2020 question paper 8465/2H

Figure 1 shows a transverse wave.

Which arrow shows the amplitude of the wave?

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Which arrow shows the wavelength of the wave?

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A teacher demonstrated waves on a string.

Figure 2 shows the apparatus used.

This is the method used.

1. Switch on the signal generator and vibration generator so the string vibrates up and down.

2. Move the wooden bridge until a clear wave pattern is formed between the wooden bridge and the vibration generator.

3. Use a metre rule to measure the length of the string between the wooden bridge and the vibration generator.

4. Record the frequency of the wave from the signal generator.

5. Record the number of loops in the wave pattern. The wave pattern shown in Figure 2 has one loop.

6. Change the frequency on the signal generator until a new wave pattern is formed.

7. Repeat steps 4 to 6.

Give one control variable in this demonstration.

The length of the string between the vibration generator and the wooden bridge was about 1.5 m

The teacher used a metre rule to measure the length of the string.

Suggest two reasons why making an accurate measurement was difficult.

Table 1 shows the results.

Give one conclusion about frequency and wavelength from the data in Table 1.

Each loop of the wave pattern is the length of half a wavelength.

Determine wavelength X in Table 1.

Calculate the period of the wave when the frequency was 30 Hz

Give your answer to 2 significant figures.

Use the Physics Equations Sheet.

Plants absorb light to photosynthesise.

Complete the word equation for photosynthesis.

Light intensity affects the rate of photosynthesis.

Figure 3 shows some of the equipment used to measure the rate of photosynthesis.

Describe a method to investigate the effect of light intensity on the rate of photosynthesis.

Use the equipment in Figure 3 and other laboratory equipment.

Algal cells photosynthesise.

Scientists investigated the effect of light intensity on algal cells.

The algal cells were placed in different light intensities.

Table 2 shows the number of extra algal cells after two days.

The initial number of algal cells was 200 000

Calculate the total number of algal cells after two days when the light intensity was 500 lux

Plot the data from Table 2 on Figure 4.

The first two points have been plotted.

Draw a line of best fit.

Give two conclusions from the results.

Use information from Table 2.

Explain how an increase in temperature from 20 °C to 25 °C would affect the number of algal cells.

Water is cycled through the environment.

Rain provides fresh water.

Fresh water in the ground contains small amounts of dissolved substances.

Suggest one source of these dissolved substances.

Figure 5 shows the total monthly rainfall from November 2017 to October 2018 in the UK.

Give two conclusions you can make from the data shown in Figure 5.

Determine the percentage increase in rainfall in the month of January 2018 compared to the month of November 2017.

Suggest one reason why scientists cannot accurately predict the total rainfall in the UK for November 2020.

A student produced distilled water from fresh water.

Figure 6 shows the apparatus used.

The student stated that the thermometer measured the boiling point of water.

The reading on the thermometer was 102 ºC

Describe how the apparatus can be changed to obtain the correct value for the boiling point of water.

Give one reason why the change is needed to obtain the correct value.

The student collected less distilled water than expected from a sample of fresh water.

Suggest one change to the apparatus to increase the volume of distilled water collected from the fresh water sample.

Give one reason why this suggestion would increase the volume of distilled water collected.

Sea water in some parts of the world is used to produce potable water.

Distillation can be used to desalinate sea water.

Explain one disadvantage of using distillation to obtain potable water.

Name one other method used for desalination.

Do not refer to distillation in your answer.

Figure 7 shows part of a food web.

There are four levels of feeding relationship shown in the food web in Figure 7.

Algae are at level 1 in the food web.

Why is it difficult to identify the level of the loggerhead turtle in the food web?

Explain the effects a decrease in the population of clams could have on the other organisms in Figure 7.

Female loggerhead turtles lay their eggs in nests on sandy beaches.

Table 3 shows how the temperature of the nest affects the sex of the loggerhead turtles.

Explain how the continued use of fossil fuels could affect the population of loggerhead turtles.

Use information from Table 3.

Two 18-year-old male students measured their reaction times.

The students used two methods, Method 1 and Method 2.

Method 1

1. Sit in front of a tablet computer.

2. When the tablet makes a sound, touch the tablet screen as quickly as possible.

3. Record the reaction time shown on the tablet.

4. Repeat steps 1 to 3 another two times.

Method 2

1. Hold a metre rule so the bottom of the rule is level with the top of the other student’s thumb.

2. Let go of the metre rule.

3. The other student catches the metre rule.

4. Record the position of the student’s thumb on the metre rule.

5. Convert the position on the metre rule to a reaction time using a conversion table.

6. Repeat steps 1 to 5 another two times.

Table 4 shows the results.

Student A and student B had different reaction times.

Suggest two reasons why student A ’s reaction time was longer than student B ’s reaction time.

Give two reasons why Method 1 would give more accurate results than Method 2.

In Method 1 the students react to a sound.

In Method 2 the students react when they see the metre rule drop.

A sound wave is a longitudinal wave.

Visible light is a transverse wave.

Describe the difference between a longitudinal wave and a transverse wave.

The nervous system coordinates reflex actions.

A person accidentally touches a hot object.

The person moves their hand away quickly.

Describe how information about the hot object is detected, and how the information reaches the muscles in the arm.

This question is about breathing and gas exchange.

Figure 8 shows a person using a peak flow meter.

Peak flow is how quickly air can be breathed out of the lungs.

Table 5 shows the peak flow of a person on two different days.

The person has different peak flow results on Day 1 and Day 2.

Suggest one reason why peak flow was lower on the second day.

Calculate value X for Day 2.

Figure 9 shows part of the lungs.

There are many alveoli in the lungs.

Alveoli provide a large surface area for gas exchange.

Explain how two other adaptations of the alveoli allow efficient gas exchange.

Do not refer to surface area in your answer.

Endocrine glands produce hormones.

Which hormone stimulates basal metabolic rate?

Figure 10 shows how concentrations of sex hormones in the blood vary during a 28-day menstrual cycle.

Which hormone does X represent?

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Which hormone does Z represent?

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Describe two effects of oestrogen between day 10 and day 12 of the menstrual cycle.

In vitro fertilisation (IVF) is a fertility treatment.

Hormones are used in IVF treatment.

Explain how different hormones are used to help a woman become pregnant.

Table 6 shows information about IVF success rates.

A 35-year-old woman with fertility problems wants a child.

Suggest why she should start IVF treatment as soon as possible.

You must include data from Table 6 in your answer.

A scientist investigated the effect of exercise on reducing the risk of some medical conditions.

The investigation involved two groups of people.

One group walked quickly and the other group ran.

The people in the walking group exercised for more time than the people in the running group.

Each group transferred the same amount of energy.

Table 7 shows data from the investigation.

Name two factors that should be controlled.

Do not refer to amount of energy transferred, age or sex in your answer.

Blood pressure measures how hard the blood is forced against the walls of the arteries.

Regular exercise makes the heart muscle stronger.

A stronger heart can pump more blood with less effort so the forces on the walls of the arteries decrease.

Suggest why walking reduces the risk of high blood pressure more than running reduces the risk of high blood pressure.

Explain how a high concentration of cholesterol in the blood can cause coronary heart disease.

A student walked quickly for 15 minutes.

Figure 11 shows the effect walking quickly had on the student’s heart rate.

Determine the rate of increase in heart rate of the student at 8.5 minutes.

Use Figure 11.

Explain why heart rate needs to increase during exercise.

Bananas from wild banana plants are not eaten by humans.

Edible banana plants are grown commercially.

Humans can eat bananas from edible banana plants because they do not contain seeds.

The edible banana plant evolved from the wild banana plant.

Figure 12 shows how scientists think the edible banana plant may have evolved.

What is process X in Figure 12 ?

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Explain why the edible banana plant cannot produce gametes.

Cloning is used to reproduce edible banana plants.

The cloned cells divide by mitosis.

Describe the process of mitosis.

Banana plants can become infected by the TR4 fungus.

The fungus enters the plant through the roots and grows within the xylem vessels.

The xylem vessels become blocked and the leaves turn yellow.

Describe why blockage of the xylem vessels causes the leaves to turn yellow.

TR4 fungus is a threat to the global banana industry.

Some wild banana plants have a gene for resistance to the TR4 fungus.

What could scientists do to protect edible banana plants from the TR4 fungus?

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