OCR GCSE Biology B (21st Century) Depth in Biology Foundation June 2023 question paper J257/02

Fig. 1.1 shows parts of the human nervous system.

Structure A allows us to sense the things we touch.

What is the name of structure A ?

CNS
Effector
Motor neuron
Sensory neuron

The muscle contracts to move the arm when it receives a nerve impulse from the brain.

What type of structure is the muscle?

CNS
Effector
Motor neuron
Sensory neuron

Structure B carries nerve impulses from the brain to the muscle.

What is the name of structure B ?

Motor neuron
Reflex arc
Sensory neuron
Synapse

Fig. 1.2 shows a diagram of the human brain.

Draw lines to connect each part of the brain with the function it controls.

The things we eat and drink are processed by our body.

Complete the sentences to describe what happens in our body when we drink water.

Use words from the list.

active transport circulatory digestive excretory heart

kidney osmosis oxygen pancreas water urea

Water is absorbed into the blood from the........ system.

Some of the water moves into and out of cells by........

The blood is filtered by an organ called the........

This organ filters water and........ out of the blood.

This organ then reabsorbs as much........ as the body needs to stay healthy.

A student says, “I think cutting all the sugar and fatty acids out of my diet will be good for me.”

The student is wrong.

Explain how the student’s body cells use sugar and fatty acids.

The student’s body cells also need amino acids.

Explain what the student’s body cells make using amino acids and how their genome is involved.

Where is the genome stored in the student’s cells?

The genome is made of DNA.

Complete the sentence to describe the structure of DNA.

DNA is a polymer made from two / four different nucleotides in a single / double helix.

Zayn investigates if cress plants grow towards the light.

Zayn puts 200 cress seeds in a tray of damp soil and places the tray directly underneath a bright lamp. The tray is labelled Tray 1.

The diagram shows the cress in Tray 1 after 7 days under the lamp.

Zayn puts 200 cress seeds in another tray of damp soil and places the tray next to the window. This is Tray 2.

After 7 days:

• 40 of the 200 seedlings in Tray 2 grew straight up

• 10 of the 200 seedlings in Tray 2 grew curved away from the window

Complete Table 3.2 by calculating the percentage of seedlings in Tray 2 that grew straight up.

Table 3.2

At the start of the investigation, Zayn wrote a prediction.

Prediction: The cress seedlings will grow towards bright light.

Explain how the results from both Tray 1 and Tray 2 support Zayn’s prediction.

Use information from Table 3.1 and Table 3.2.

Tray 1 and Tray 2 were both left in the light for 7 days.

Describe two things that could have caused the amount of light received by the seedlings in Tray 2 to change over the 7 days.

Describe one way Zayn could have controlled the amount of light received by the seedlings in Tray 2.

Which process caused the seedlings in Tray 2 to curve towards the window?

Tick (✓) one box.

State the name of the plant hormone that caused the seedlings in Tray 2 to curve towards the window.

Leo is a 52-year-old man. He is having a health check-up.

What can you conclude about Leo’s blood pressure from Fig. 4.1 ?

Leo’s diastolic pressure remains at 76 mmHg.

What range of systolic blood pressure would be ideal blood pressure for Leo?

Ideal systolic blood pressure range =........ to........ mmHg

High blood pressure is one factor that increases the risk of cardiovascular disease (CVD). Other factors also increase this risk.

Fig. 4.2 shows data on the average amount of fat eaten and the number of deaths due to CVD in one year in a sample of 100 000 people from the UK.

Average amount of fat eaten (% of diet)

Describe the trend in the data, using Fig. 4.2.

Explain how the amount of fat eaten could have an effect on the number of deaths due to CVD.

Use ideas about changes in the body caused by eating fat.

Fig. 4.2 shows data from a sample of 100 000 people.

What groups of people would you expect to be included in the sample to make it representative of the whole population of the UK?

In this sample of 100 000 people, 3934 people died of CVD in one year.

Calculate how many people you would expect to die in the UK population from CVD in one year.

The UK population is 60 000 000.

The doctor makes some notes about Leo.

• Blood pressure: 141/76 mmHg

• Amount of fat eaten: 22% of diet

• Occupation: Office worker (drives to work)

Suggest two lifestyle changes Leo could make, other than taking medicine, to reduce his risk of CVD.

Leo is worried about taking medicine to treat his CVD.

Complete the table by describing how the medicine was tested.

Identify one risk for Leo if he takes the medicine.

Without medicine and lifestyle changes, Leo may need heart surgery.

Evaluate the use of lifestyle changes to treat Leo compared with the use of surgery.

Species evolve over time. This evolution can be explained using ideas about the process of natural selection.

Read the article.

One species of hummingbird called a swordbill is the only bird that has a beak longer than its body. It is the most common species of hummingbird in one region of South America.

This region is the only place where a species of plant called a passionflower grows. The passionflower has a long tube with nectar at the bottom. Swordbills feed on the nectar.

* Explain why the swordbill has become the most common species of hummingbird in the region where this passionflower grows.

Use ideas about natural selection in your answer.

Humans are chopping down trees in which the swordbill hummingbird lives. This could cause a large decrease in the size of the swordbill population.

Explain how two other factors could cause a decrease in the size of the swordbill population.

When swordbill hummingbirds feed on the nectar, they transfer pollen between passionflowers. The pollen contains the male gametes of the passionflowers.

Explain why chopping down the trees in which the hummingbirds live could put the passionflowers in danger of extinction.

Darwin and Wallace suggested that natural selection could be an explanation for the evolution of species.

Describe two pieces of evidence that helped them to develop their explanation.

Which two statements explain the impacts of Darwin and Wallace’s explanation for the evolution of species?

Tick (✓) two boxes.

A type of bacteria uses an enzyme to digest nylon. Nylon was invented in 1935.

Scientists think this new enzyme only appeared in bacteria after 1935.

Describe the changes in the bacteria that allowed them to make the new enzyme.

A scientist cuts a thin slice from a plant stem, as shown in Fig. 6.1.

The slice of stem contains three different tissues.

Draw lines to connect the description of each tissue with its correct name.

One has been done for you.

Statements A to E describe steps the scientist uses to look at the slide under the microscope.

They are not in the correct order.

A Place the slide on the stage.

B Look into the eyepiece lens.

C Use the coarse focus control to move the objective lens down towards the stage.

D Use the fine focus control to move the objective lens until the image is as clear as possible.

E Use the coarse focus control to move the objective lens upwards until the image is clear.

Write the letters in the boxes to describe the correct order of the steps.

One has been done for you.

Suggest two ways the scientist can work safely when using the microscope.

Fig. 6.3 shows part of the slice of stem. One of the cells is dividing by mitosis.

The chromosomes in the labelled dividing cell are clearly visible and appear dark.

Describe what the scientist added to the slide to make the chromosomes clearly visible.

To get the image in Fig. 6.3 the scientist used an eyepiece lens with a magnification of 10, and an objective lens with a magnification of 40.

Describe how to calculate the total magnification.

One of the dividing cells in Fig. 6.3 has a width of 10 m.

What is 10 m to the nearest order of magnitude?

10⁰m 10¹m 10²m 10³m

In the dividing cell, a single chromosome has a width of 0.01 m.

How many orders of magnitude larger is the cell than the single chromosome?

3 30 100 1000

Plant cells in the leaf of a tree contain chloroplasts and mitochondria.

Complete the sentences about the processes that take place in chloroplasts and mitochondria.

Use words from the list.

cellular respiration meiosis photosynthesis transpiration

In the chloroplasts, glucose is made by........

The glucose is used in the mitochondria in........

The process of cellular respiration takes place continuously in plant cells.

Explain why it has to take place continuously.