OCR GCSE Biology A (Gateway) Paper 2 Foundation June 2019 question paper J247/02

Which of these is an abiotic factor that can affect organisms?

A Food availability

B Light intensity

C Pathogens

D Predators

Your answer

The diagram shows the water cycle.

Which label, A, B, C or D, represents evaporation?

Your answer

Which combination of gametes will produce a male baby?

A A sperm with XY chromosomes and an egg with XX chromosomes.

B A sperm with one X chromosome and an egg with one Y chromosome.

C A sperm with one Y chromosome and an egg with one X chromosome.

D A sperm with XX chromosomes and an egg with XY chromosomes.

Your answer

Why are stem cells useful for repairing damaged tissues?

A They are easily obtained from any organ.

B They are not attacked by pathogens such as bacteria.

C They are haploid.

D They can divide to form different types of cell.

Your answer

Which relationship describes an organism living on an animal and harming it?

A Decomposition

B Mutualism

C Parasitism

D Predation

Your answer

Most food chains only have a maximum of five trophic levels.

Explain why.

A Organisms always get larger at higher trophic levels.

B Energy is lost at each trophic level.

C It is more energy efficient to eat meat than plant material.

D The number of organisms feeding always increases at higher trophic levels.

Your answer

Which of these is an example of discontinuous variation?

A Body weight

B Hand span

C Height

D Sex

Your answer

The prickly pear is a cactus plant that was introduced into Australia.

The prickly pear cactus spread across the country.

To control the spread of the prickly pear cactus, a caterpillar was released to eat it.

What is the name of this type of control?

A Biodiversity

B Biological

C Mutualism

D Pesticide

Your answer

Which statement about health is true?

A Health is the absence of disease.

B A person who is free from disease must be healthy.

C A person can have a serious disease and be healthy.

D A person can be free from disease and not be in good health.

Your answer

Which of these gives a correct risk factor for the named disease?

Your answer

Cystic fibrosis is a genetic condition caused by a recessive allele (f).

Which is the genotype of a person with cystic fibrosis?

A Heterozygous and ff

B Heterozygous and Ff

C Homozygous and ff

D Homozygous and FF

Your answer

Each cell in the eye of a kangaroo has 16 chromosomes.

How many chromosomes are there in one kangaroo sperm cell ?

A 4

B 8

C 16

D 32

Your answer

What do most vaccines contain?

A Antivirals

B Dead or weakened pathogens

C Specific antibiotics

D White blood cells

Your answer

A student estimates the number of snails in a pond. Part of his method involves collecting snails and marking them.

What is the name of the method he is using?

A Aseptic technique

B Capture-recapture

C Percentage increase

D Scaling-up

Your answer

Look at the bacterial cell that causes disease in humans.

The human eye can see objects 0.1 mm in size.

What minimum magnification will be needed before the eye can see this bacterial cell?

A 12.5×

B 125×

C 1250×

D 12500×

Your answer

This question is about selective breeding.

Cows are female and are used by farmers to produce milk.

Bulls are male.

Look at the details of different varieties of cows and bulls.

A farmer wants to produce cows that produce a high yield of creamy milk.

He does not want his animals to be aggressive.

Suggest which cow and bull he should choose to mate with each other.

Explain your answer.

Describe the relationship between number of cows and yield of milk shown in the graph.

Suggest two reasons for the relationship shown in the graph.

Over the whole world the demand for food to feed humans is increasing.

Describe why is there an increasing demand for food.

Genetic modification (GM) is one method that humans are using to try and produce more food.

What is genetic modification?

Scientists can use GM to alter the features of crops.

One feature is crop yield.

Suggest two other features of crops they could change.

In a recent survey 200 people were asked about GM crops.

The people surveyed were shown six statements. Three were negative statements and three were positive statements.

They were asked to choose one statement they agreed with.

These are the results.

Calculate the percentage of people in the survey that have a negative opinion of genetic modification.

Some people get very painful headaches called migraines. Scientists think that these are caused by a protein in the brain called CGRP. Levels of the CGRP protein are higher in the brains of people who get migraines.

Doctors are trying to find a treatment to prevent migraines. They have produced an antibody against the CGRP protein.

Complete these sentences to describe how antibodies are made in the body.

Use words from the list.

Each word can be used once, more than once, or not at all.

antibiotics antigens antivirals

platelets red blood cells white blood cells

Foreign cells have chemical groups on their surface called........

These chemical groups are detected by........ which then produce

antibodies.

The doctors test the antibody treatment on migraine patients.

The patients are divided into two groups:

• One group is given an injection of the antibody.

• The second group receives an injection of a placebo which does not contain the antibody.

They record the mean number of days each patient had migraines before and after treatment.

The table shows their results.

The placebo group does not receive the antibody.

Suggest why this group is included in the study.

The total number of migraine days for the patients on the placebo after treatment was 480.

The mean number of migraine days per patient after treatment was 6.4.

Calculate the number of patients in the placebo group.

Explain why it is important that a second group of doctors should repeat this test.

A salt marsh is a large, muddy area of land where a river joins the sea.

When the tide comes in, the salt marsh gets covered with seawater.

Suggest one reason why salt marshes are difficult places for plants to grow.

Student A and student B study the plants growing on a salt marsh.

They both sample the plants present by laying out two tape measures at right angles across the salt marsh.

They then place a square frame on the ground in different places and count the number of plants in the square, as shown below.

What is the name of the square frame that they use to sample the plants?

The diagrams show the position of each student’s samples across the salt marsh. Each small square in the diagrams represents one sample.

The whole salt marsh has an area of 2500 m². (i)

Each square frame has an area of 0.25 m².

Calculate the percentage of the whole salt marsh that was sampled by student A.

Look at the two students’ sampling shown in the diagrams.

Explain which student is likely to get the most accurate estimate for the number of plants in the salt marsh.

Their teacher said that they should take care as there may be harmful bacteria in the salt marsh.

State two things that the students could do to reduce the risk of infection from the harmful bacteria.

* In some salt marshes large sand banks have been built. These stop tides from entering the salt marsh. The level of soil on the salt marsh builds up and the marsh turns into dry land.

Local farmers want to turn salt marshes into dry land and other people want to leave it as a salt marsh.

Explain why. Use ideas about land use and biodiversity in your answer.

Rats are a major pest in many areas of the world. They can reduce food security and spread diseases.

Warfarin is a chemical that is used as a rat poison. It stops platelets working in the blood.

Describe the function of platelets in the blood.

Some rats are resistant to warfarin. When fed with large amounts of warfarin the rats do not die.

Scientists found that the resistance is due to the dominant allele R.

Two resistant rats (Rr) mate.

Complete this genetic diagram to find the ratio of resistant rats to non-resistant rats that would be expected to be produced.

After several years, the percentage of resistant rats in the population had increased.

Use Darwin’s theory of natural selection to explain this observation.

Scientists are now trying to find another poison to use on rats.

They have introduced a chemical called phosphine. This blocks the action of mitochondria in rat cells.

Explain why this might kill rats.

Animals and plants can get different types of diseases.

Look at the list of four diseases.

AIDS

Type 2 diabetes

Crown gall disease

Barley powdery mildew

Write each disease in the correct column of this table.

Sinusitis is an infection that can be caused by bacteria or viruses.

Sinusitis causes a runny nose and bad headaches.

Doctors only give antibiotics to patients with these symptoms if they are sure their illness is caused by bacteria.

Write down two reasons why.

Look at the graph. It shows the length of time that patients show symptoms of sinusitis.

Doctors usually wait 14 days after infection before giving patients antibiotics for sinusitis.

Use the graph to explain why.

The diagram shows part of a food web from a woodland.

Great tits are described as both primary consumers and secondary consumers.

Explain why.

Foxes are described as both predators and competitors of pine martens.

Explain why.

Which organism in the food web occupies the second trophic level?

Great tits and flycatchers are both birds.

In a conservation project, scientists have built boxes for the birds to nest in. The scientists fixed the boxes on trees at different heights.

The table shows how many birds of each type used the boxes for nesting.

Draw a bar chart on the graph paper to show the scientists’ results.

The results for great tits and flycatchers should be on the same axis.

The food web shows:

• Weasels feed on great tits

• Pine martens feed on flycatchers.

Weasels live on the ground but pine martens live in trees.

How can this be used to explain the results of the scientists’ investigation?

Scientists investigated if crops can be grown on the planet Mars.

They used a soil that was similar to the soil found on Mars. The soil contained some minerals but no living organisms.

The scientists managed to grow crops in the soil. However on Mars, the minerals in the soil would soon run out.

Explain why.

Living organisms could be added to the soil but there is no air on Mars. The plants would need to be grown in an enclosed structure.

At first, air would need to be added, but after a while the organisms in the soil and the plants would supply each other with the gases they need.

Explain how this would happen.