AQA GCSE Synergy Paper 2: Life and environmental sciences Higher June 2025 question paper 8465/2H

Figure 1 shows a human egg cell viewed using a light microscope.

In Figure 1, the diameter of the image of the egg is 38 mm.

The magnification of Figure 1 is × 400

Calculate the real diameter of the egg cell in micrometres.

Use the equation:

1 millimetre = 1000 micrometres

Real diameter of egg cell = _____________________ micrometres

Draw a simple diagram of the egg cell shown in Figure 1.

On your drawing:

$l~bel two parts of the egg cell that are visible in Figure 1

$do not include other cells.

Some parts of a human egg cell are not visible in Figure 1.

Name one part of a human egg cell that is only visible using an electron microscope.

Name the process of cell division that produces egg cells.

How many chromosomes are in a human egg cell?

Describe how a chromosome in a sperm cell determines whether the offspring that forms is male or female.

Which hormone stimulates the release of an egg?

Tick () one box.

FSH

LH

Oestrogen

Oral contraceptive pills contain hormones that prevent the release of an egg.

Scientists studied the effectiveness of different types of contraception with perfect use and with use in real life.

‘Perfect use’ means following all the instructions.

‘Use in real life’ is what actually happens in the population. The instructions may not always be followed in real life.

Figure 2 shows the results.

Evaluate the effectiveness of the three types of contraception shown in Figure 2.

Use data from Figure 2.

A student investigated the emission of infrared radiation.

Figure 3 shows some of the equipment used.

This is the method used.

1. Measure and then pour a volume of 100 cm³ of very hot water into each can.

2. Place a lid on each can and insert a thermometer through each lid.

3. Record the initial temperature of the water in each can.

4. Record the temperature of the water in each can after 5 minutes.

The student had two different types of thermometer that could have been used.

Figure 4 shows the readings on the two thermometers before being used in the investigation.

Give two advantages of using thermometer A compared with using thermometer B.

2

The student used thermometer A for all the temperature measurements.

Table 1 shows the results.

The student repeated the investigation to observe how the temperature of the water in the can varied with time.

The student used a temperature sensor and a datalogger.

The datalogger recorded two readings each second.

What is the advantage of using the datalogger for a cooling curve?

Tick () one box.

The datalogger recorded readings less frequently than a student could.

The datalogger recorded readings at the same frequency as a student could.

The datalogger recorded readings more frequently than a student could.

Figure 5 shows the results for the can with the matt black surface.

When did the surface of the can emit infrared radiation at the greatest rate?

Give a reason for your answer.

Use Figure 5.

Tick () one box.

At the start of the investigation

In the middle of the investigation

At the end of the investigation

Reason

The student also used a can with a matt white surface.

The initial temperature of the water in this can was 80 °C.

Draw a line on Figure 5 to show the expected results for the can with the matt white surface.

Sea water is a mixture.

Figure 6 represents water as a solid.

Describe two limitations of Figure 6 as a model of a solid.

Photosynthesis produces glucose (C₆H₁₂O₆).

Write a balanced symbol equation for photosynthesis.

A student investigated the effect of light intensity on the rate of photosynthesis in three species of aquatic plant.

Figure 7 shows the apparatus used.

This is the method used.

1. Place species A in water in a test tube.

2. Leave the test tube containing species A in a dark room for 10 minutes.

3. Put the test tube containing species A 20 cm away from the lamp.

4. Record the number of bubbles produced by species A in 5 minutes.

5. Repeat steps 2 to 4 at different distances from the lamp.

6. Repeat steps 1 to 5 using species B and species C.

The student repeated the investigation several times.

Explain how two other improvements to the method would ensure the results are more valid.

When the distance between the lamp and the plant is 20 cm, the light intensity is 0.0025 arbitrary units.

Calculate how many times greater the light intensity is at 20 cm compared with the light intensity at 60 cm.

Use the equation:

The student collected valid results.

Figure 8 shows the results.

Predict the number of bubbles that would be produced by species B at 10 cm from the lamp.

You should extend the line on Figure 8.

Species A, B and C grow at different depths in ponds.

Which species is most likely to be found growing near the surface of the pond?

Give the reason for your answer.

Tick () one box.

A B C

Global dimming is a decrease in the sunlight reaching the Earth’s surface due to particulates in the atmosphere.

Coronary heart disease (CHD) is a type of cardiovascular disease.

Stem cells can be used to treat patients who have CHD.

The stem cells differentiate into cells of coronary arteries or heart muscle cells.

A patient with CHD was treated with stem cells.

The patient said:

‘Before the treatment, I was always tired. Now I can run.

There was a gradual improvement in my health and 3 months after the treatment I felt fit.’

Stem cells for the treatment of CHD can come from the patient or from a donor.

Describe why using stem cells from the patient is more successful than using stem cells from a donor.

Radio waves are one type of electromagnetic wave.

What are two properties of all electromagnetic waves?

Tick () two boxes.

A thin sheet of metal stops all electromagnetic waves.

All electromagnetic waves are longitudinal.

All electromagnetic waves have the same speed in a vacuum.

All electromagnetic waves transfer energy.

Water reflects all electromagnetic waves.

A teacher used a radio transmitter, a metal sheet and a radio receiver to demonstrate the reflection of radio waves.

Figure 9 shows the path of the radio waves from the transmitter to the metal sheet.

The teacher placed the radio receiver at positions A, B, C and D.

Which position was the radio receiver at when the radio waves were detected?

Tick () one box.

A B C D

The frequency of the radio wave was 2400 MHz.

The speed of the radio wave was 3.0 × 10⁸ m/s.

Calculate the wavelength of the radio wave.

Use the Physics Equations Sheet.

The aerial of the receiver absorbs radio waves.

Explain why the frequency of the alternating current in the receiver circuit depends on the frequency of the radio waves.

An increase in the concentration of greenhouse gases in the atmosphere is causing global warming and climate change.

Explain: how scientists can predict future climate change

why there are uncertainties in the predictions.

Global warming increases the rate of evaporation of water from the sea.

Explain how increased evaporation could lead to an increasing rate of global warming.

You should refer to the interaction of radiation with matter in your answer.

Table 2 shows information about some greenhouse gases.

The concentration of methane in the atmosphere is greater than the concentration of CFCs.

Calculate the number of times greater.

Give your answer to 2 significant figures.

Most efforts to reduce greenhouse gases refer to carbon dioxide rather than to methane or CFCs.

Suggest why.

Use Table 2.

Fruit flies are small insects.

Figure 10 shows a fruit fly.

Fruit flies:

are easy to keep in containers

have a short time between one generation and the next generation

are used to study evolution.

A scientist studied the length of fruit fly wings and the shape of fruit fly wings.

Fruit flies with short wings usually have rounder wings than fruit flies with long wings.

Explain how fruit flies can be selectively bred to produce a population with wings that are long and round.

The scientist produced a population that only had long and round wings.

The scientist stopped selectively breeding the fruit flies.

After several more generations, the population all had short wings.

Explain why.

Scientists have produced genetically modified (GM) fruit flies.

Some fruit flies are pests of crops.

The GM fruit flies only produce male offspring.

The scientists released a large number of the GM fruit flies into the wild population.

Explain how releasing the GM fruit flies caused the population of fruit flies in the wild to decrease.

Explain the benefits and risks of releasing GM fruit flies.