Edexcel GCSE Combined Science Paper 2: Biology 2 Foundation June 2018 question paper 1SC0/2BF

Insulin is produced by an endocrine gland and is transported in the blood.

Which row shows the endocrine gland and the target organs for insulin?

Which part of the blood transports insulin to its target organs?

Figure 1 shows the blood glucose and blood insulin concentration for a healthy person during one day.

The blood glucose concentration increases after a meal.

Explain why the blood glucose concentration then decreases.

State one cause of type 1 diabetes.

Explain how controlling the diet can be used to treat type 2 diabetes.

A scientist is planning to test a new treatment for type 2 diabetes.

She selects 300 volunteers who have type 2 diabetes.

State two other factors that the scientist should consider when selecting the 300 volunteers.

Figure 2 shows alveoli from a healthy lung.

Smoking can cause a condition called emphysema.

Figure 3 shows alveoli from a person with emphysema.

Use words from the box to complete the following sentences.

breathing diffusion larger

osmosis smaller thicker

The alveoli from the person with emphysema have a_........

surface area than the alveoli from a healthy lung.

The surface area of the alveoli will affect how much oxygen moves into the blood

by the process of_........ .

The graph in Figure 4 shows the volume of oxygen an athlete absorbs at different running speeds.

Describe the trend shown in Figure 4.

Which uses more oxygen when the running speed of the athlete changes from 4 to 6 km per hour?

Explain why the athlete produces lactic acid when running at 14 km per hour.

(a) Plants use nitrate ions to make proteins and chlorophyll.

What effects will a low nitrate ion concentration in soils have on plants?

Which organisms convert nitrogen to nitrate ions during the nitrogen cycle?

Figure 5 shows part of a root as seen using a light microscope.

Figure 6 shows information about the two types of cell labelled in Figure 5.

Calculate the surface area to volume ratio of the root hair cell.

Explain the benefit to the plant of having root hair cells.

Algae are green plants.

Figure 7 shows the number of algae in a lake in the United Kingdom during one year.

Explain the changes in the number of algae in the lake from February to June.

Figure 8 shows a British glow-worm.

Read the following extract before answering the questions.

Female glow-worms produce bright lights in the summer to attract males. Glow-worm larvae are predators of slugs and snails, but adult glow-worms do not feed. Females only have a few weeks to attract a mate and lay eggs, before the females die.

What will happen if the population of snails decreases?

Female glow-worms have an enzyme called luciferase. The glow is produced when this enzyme catalyses a reaction between oxygen and a protein.

A scientist devised a plan to investigate the effect of oxygen concentration on this reaction.

The scientist had:

• five flasks of water each with a different concentration of dissolved oxygen

• a solution of the protein

• a solution of the enzyme.

The first step of this plan is:

Step 1. Add some of the protein solution to each of the five flasks.

Describe the next two steps that should be in this plan to obtain results for this investigation.

Step 2_........

Which procedure would improve the investigation?

The enzyme luciferase works best at pH 8.

Explain why the activity of the enzyme decreases at pH 5.

Female glow-worms are found attached to grass plants in a large field.

Describe a sampling technique to find the mean number of female glow-worms in 1 m² of the field.

The mean number of female glow-worms in 1 m² of the field is 5.

The field has a total area of 800 m².

Estimate the number of female glow-worms in the whole field.

(a) Figure 9 shows a diagram of a red blood cell from a turtle and a diagram of a red blood cell from a human.

These cells are animal cells.

Animal cells do not have

The actual length of the red blood cell from a turtle is 20.5 μ m.

Calculate the length of the magnified image of the red blood cell of the turtle when magnified 400 ×.

_........ μm

The width of the human red blood cell, when magnified 400 ×, is 3.08 mm.

Calculate the actual width of the cell and show your answer in standard form.

_........ mm

Red blood cells are carried in veins and arteries.

Figure 10 shows the equipment used to measure the elasticity of an artery.

Describe a method you could use to see how much the ring of tissue from an artery could stretch before it no longer returned to its original size.

Give one safety precaution you need to take when handling animal tissue such as blood vessels.

Figure 11 shows the circulatory system of a frog.

Explain why the circulatory system of a frog is less efficient at carrying oxygen to the tissues than the circulatory system of a human.

State why a coverslip is placed on top of the leaf peel.

Explain why the leaf peel rather than the whole leaf was viewed with a microscope.

The student drew a biological diagram of the leaf peel taken from the underside of the leaf.

Figure 13 shows this diagram.

State the number of stomata visible on Figure 13.

The student observed that the stomata were open.

Describe how stomata open.

*(c) Figure 14 shows xylem and phloem. Xylem and phloem are involved in the transport of substances through a plant.

Use Figure 14 to help you describe how water and sucrose move through a plant.