OCR GCSE Combined Science A (Gateway) Biology Paper 2 Foundation June 2024 question paper J250/02

What traps harmful microorganisms in human lungs?

A Acid

B Hairs

C Mucus

D Plasma

A student investigates the number of plant species growing in one area.

Which piece of scientific equipment will they use?

A Balance

B pH probe

C Pooter

D Quadrat

Scientists test the effect of new drugs on the growth of a pathogen.

Which new drug has no effect on the growth of the pathogen?

Which word describes all the physical features and living organisms in an area?

A Community

B Ecosystem

C Habitat

D Interdependence

Eye colour, height and weight in humans all show variation.

Which of these are examples of continuous variation?

A Eye colour and height

B Eye colour, height and weight

C Height and weight

D Height only

Which process is required to recycle both carbon and nitrogen?

A Condensation

B Decomposition

C Photosynthesis

D Precipitation

Which risk is decreased by using adult stem cells instead of embryonic stem cells in skin transplants?

A Fatty deposits forming below the skin

B Rejection of transplanted skin

C Skin becomes less waterproof

D Skin cancer developing

The diagram shows a phylogenetic tree for a group of related animals.

Which two animals are most closely related?

A Aardwolf and spotted hyena

B Aardwolf and striped hyena

C Brown hyena and spotted hyena

D Brown hyena and striped hyena

Gardeners are changing the way they care for their gardens.

Which change would increase biodiversity?

A Adding chemical fertilisers to a grass lawn

B Cutting a grass lawn more often than usual

C Removing a grass lawn area and putting down paving stones

D Replacing a grass lawn area with a wild flower meadow

Inheritance is passing genetic material from one generation to the next.

Which terms describe sex cells in humans?

Tick (✓) two boxes.

Peas develop inside pods.

Pea pods can be green or yellow.

A pea plant with green pods is crossed with a pea plant with yellow pods. All the pods on the new plant are green.

Complete the sentences about the pea pods.

Use words from the list.

dominant haploid heterozygous

homozygous recessive

The results of this cross show that the allele for green is........ and the

allele for yellow is........

The genotype of the new plant is Gg. This means it is........ for pod

colour.

The new plants with green pods are then crossed.

What is the probability that a plant from this cross will have yellow pods?

Complete the genetic diagram to explain your answer.

The picture shows the plant pathogen that causes powdery mildew.

Why is powdery mildew called a communicable disease ?

Describe how selective breeding is used to make plants resistant to powdery mildew.

New medicines are developed all the time.

Insulin is a protein used to treat diabetes. The human stomach contains an enzyme that is specific to proteins like insulin.

Suggest why it is difficult to develop an insulin medicine that is swallowed.

Which type of medicine has been developed to treat HIV?

antibiotic antigen antiseptic antiviral

Some diseases are treated by changes to lifestyle.

Complete these sentences about cardiovascular disease.

The risk of cardiovascular disease is reduced by a........ low in saturated fat.

This reduces the risk of blocked arteries therefore allowing more oxygen to be transported to the

........ muscle in the ventricle wall.

The moisture content in soil affects the growth of plants.

A student investigates the moisture content of different soils.

This is the method they use:

• Measure the mass of each soil sample.

• Place the soil samples in a warm oven to dry for 4 hours.

• Measure the mass of each soil sample again.

The table shows their results.

Calculate the change in mass for each soil sample.

Write your answers in the table. Give all answers to the same number of decimal places.

The student uses the changes in mass to conclude that soil sample B had the highest percentage moisture content.

Suggest why the student cannot make a fair comparison between the samples.

Describe two ways the student could improve their investigation to get a valid conclusion.

Explain how low moisture content in soil affects transpiration in plants.

Moisture content is one abiotic factor that affects plants.

State two other abiotic factors that affect plant growth.

15* The graph shows the changes in population of a predator and its prey.

Describe and explain the trends in the graph. Identify the predator and the prey using evidence from the graph to support your choice.

Scientists are concerned that increased pollution in a forest is affecting the population of insects living in the forest.

In an investigation, scientists estimated the population of flying insects in a forest.

• They trap the insects using nets.

• The mass of insects collected each month is then recorded. The data is collected in two different years, 1995 and 2015.

The table shows their results.

Complete the bar chart to show the mass of insects collected each year. Both years should be included on the same grid. Include a Key to identify which year the bars represent.

What two conclusions can be made about the mass of flying insects in 1995 compared to 2015?

How can the scientists’ method be developed to investigate biodiversity in the forest?

In a separate investigation, scientists estimated the population of insects that live on the forest ground.

The scientists trap insects using a pitfall trap. This is a hole in the ground that the insects fall into when they crawl along the ground.

For each estimate they use this method:

• Place pitfall traps in different areas of the forest.

• Count the total number of insects caught in the pitfall traps.

• Mark the insects.

• Release the insects where they are collected from.

A week later they trap a second sample of insects.

The scientists used an ink that is not easily washed off to mark the insects for identification.

State one other precaution that they should take when deciding how to mark the insects.

They complete their investigation during July 1995 and July 2015. This table shows the results of this investigation.

The scientists use this formula to estimate the population of insects living on the forest ground:

The population of insects in 1995 is estimated to be 855.

Use the formula to estimate the population size of insects in 2015. Give your answer to 3 significant figures.

The aim of each investigation is to see if increased pollution has affected the insect population.

The population of insects living on the forest ground increased between 1995 and 2015.

Which statements about the two investigations are true, and which are false ?

Tick (✓) one box in each row.