Edexcel GCSE Biology Paper 2 Higher June 2024 question paper 1BI0/2H

1 (a) Banting and Best were the first scientists to use the hormone insulin for the treatment of diabetes. They extracted insulin from the body organs of animals.

(i) Which body organ produces insulin?

(ii) How does insulin travel to its target organ?

(b) Tasting urine was one of the first ways doctors tested for diabetes. If the urine tasted sweet, the patient may have diabetes. Describe the chemical test we now use to test for glucose in urine.

(c) A scientist wanted to compare the glucose concentration in two urine samples. State two variables that need to be controlled for the comparison to be valid.

2 A centrifuge can be used to separate the different parts of human blood. Figure 1 shows blood separated into different parts.

(a) (i) Name part X.

(ii) Which substance, needed for cellular respiration, is carried by red blood cells?

(iii) Name two types of white blood cell.

(b) (i) When a person donates blood, 470 cm³ of blood is removed from their body. Red blood cells make up 44 % by volume of the blood. Calculate the volume of red blood cells in 470 cm³ of donated blood. Give your answer to the nearest whole number.

(ii) Before donating blood, a person has a small blood sample taken to check that the blood is healthy. State two precautions a doctor should take when collecting this sample.

3 (a) Figure 2 shows a root hair cell from a plant.

(i) Name the part labelled X.

(ii) State one way that the structure of the root hair cell increases the volume of substances it absorbs.

(iii) Explain why root hair cells do not contain chloroplasts.

from the Elodea cells in tap water.

(ii) Explain why placing the Elodea cells in the 10% salt solution causes the changes seen in Figure 3.

4 A student investigated the decomposition of two different types of leaf. The student placed 200 grams of holly leaves in a net bag. The student placed 200 grams of oak leaves in another net bag. The bags were left in a classroom. The mass of the leaves in each bag was recorded every 10 days for 50 days.

(a) State two variables that would need to be controlled in this investigation.

(b) The results of this investigation are shown in Figure 4.

Figure 4

(i) Calculate the rate of decomposition of holly leaves from 0 to 50 days.

(ii) Compare the trends shown in the data for holly leaves and oak leaves.

(c) Explain why it is important for the environment that dead leaves are decomposed.

(d) Name one type of organism that decomposes leaves.

(e) Leaves are eaten by snails. 1 600 grams of leaves and 10 snails were kept in a container for one month. A scientist measured the mass of the leaves and the mass of the snails at the start and end of one month. Figure 5 shows the results.

Explain why the change in mass of the leaves is not the same as the change in mass of the snails.

5 (a) A scientist decided to study the variety of living organisms in a garden.

(i) The scientist wanted to use a random sampling technique. Devise a plan the scientist could use to randomly sample the number of plant species in the garden.

(ii) The scientist also measured abiotic factors in the garden. The pH of the soil was measured using a pH meter. Describe how three other abiotic factors could be measured in the garden.

(iii) Mistletoe is a parasite that grows on some trees. Figure 6 shows a tree with mistletoe growing on it.

(Source: © NagyDodo/Shutterstock)

Figure 6

Describe the feeding relationship between the mistletoe and the tree.

(b) Nitrate fertilisers are used in the garden. Explain why nitrate fertilisers are used in gardens.

6 A student investigated the effect of glucose concentration on the rate of anaerobic respiration in yeast.

(a) The student used five concentrations of glucose: 5 %, 10 %, 15 %, 20 % and 25 %. A teaspoon of dried yeast was added to 20 cm³ of the 5 % glucose concentration in a measuring cylinder. A drop of washing up liquid was added and the mixture was stirred. A reaction occurred and bubbles collected as foam on the surface of the mixture. The height of the foam was measured after five minutes. This method was repeated for each concentration of glucose.

(i) Describe how to set up a control for this investigation.

(ii) State how the scientist could improve this investigation to increase the rate of the reaction.

(b) The results of this investigation are shown in Figure 7.

Figure 7

(i) The student thought one of the results was anomalous. Explain which of these results is anomalous.

(ii) Explain why the height of the foam was greatest for the 25 % glucose concentration.

7 A farmer wants to make sunflower seeds germinate faster.

(a) Which is the best hormone for the farmer to use?

(b) The sunflower plants grew and flowered. The farmer noticed that the flowers faced a different direction at different times of the day. Figure 8 shows a sunflower at different times of the day. This movement is an example of phototropism.

(Source: © yevgeniy11/Shutterstock)

Figure 8

(i) This movement of the flower was in response to the light. Explain how the sunflower changed direction throughout the day.

(ii) Explain how water moves through the stem of the sunflower plant to the leaves.

(iii) Sunflower leaves are large. Explain why large leaves are an advantage to the plant.

8 (a) Figure 9 shows a human heart.

(i) Draw arrows on Figure 9 to show the direction of blood flow through the left side of the heart.

(ii) Name the main blood vessel that carries deoxygenated blood into the heart.

(b) Figure 10 shows the heart rate and stroke volume of a person when at rest and when doing exercise.

Figure 10

(i) Calculate the difference in cardiac output when at rest and when doing exercise. Give your answer to 3 significant figures and include units in your answer.

(ii) Explain why the cardiac output needs to increase during exercise.

9 (a) The female contraceptive pill contains hormones to prevent pregnancy.

(i) Which hormones are in the female combined contraceptive pill?

(ii) Explain how the hormones in contraceptive pills prevent ovulation.

(iii) Explain how a barrier method of contraception prevents pregnancy.

*(b) Hormones can be used as part of assisted reproductive technology. Explain how assisted reproductive technology (ART) can be used to increase the chances of a woman becoming pregnant.

10 (a) Figure 11 shows the location of the liver and kidneys in the human body.

(Source: © Magic mine/Shutterstock)

Figure 11

(i) The liver breaks down substances in the body to form waste products. Which row of the table is correct?

(ii) State how the waste products travel from the liver to the kidneys.

(b) A scientist investigated the effect of a high-protein, low-carbohydrate diet on a person’s body. The scientist measured the concentration of substances found in the urine of a person on this diet (person A) and in the urine of a person not on this diet (person B). The results are shown in Figure 12.

Figure 12

(i) Evaluate the results shown in Figure 12.

*(ii) Explain how a nephron ensures that there is no protein and no glucose in the urine of person A.