5090_s24_qp_21
A paper of Biology, 5090
Questions:
6
Year:
2024
Paper:
2
Variant:
1
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1
The lungs are part of the human gas exchange system. Breathing moves air into and out of the lungs. shows parts of the human gas exchange system and their functions. On , draw a line from each part to its function. One has already been done for you. part function intercostal muscles goblet cells alveoli cilia trachea exchange gases remove pathogens carry air to bronchi change volume of thorax release mucus State two features of alveoli that make them suitable for gas exchange. Gas exchange changes the percentages of some gases in the lungs. The pie charts in show how the percentages of gases in the lungs change during one breath. Complete the pie chart titles and the key which shows which gases are represented by different types of shading. air air key other gases
9. Human gas exchange  →  9.1. Human gas exchange
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2
Brown bread, made from the flour of whole wheat grains, contains both starch and fibre. A man eats a piece of brown bread. In his digestive system, the starch in the bread is chemically digested to maltose and then to glucose. Describe where and how this digestion takes place as the bread travels through his digestive system. Describe what happens to the fibre as it passes through his digestive system. Glucose passes from the digestive system into the blood by diffusion and active transport. Give two ways in which active transport is different from diffusion. Scientists have found that there are different types of starch which have molecules of different shapes. Some molecules are digested rapidly and others are digested slowly. The graph in shows the effect on the concentration of glucose in the blood after eating two types of starch. blood glucose concentration time / hours starch eaten key rapidly digested starch slowly digested starch There is already glucose in the blood when the starch is eaten. Explain how shows this. Both graph lines show an initial increase in blood glucose concentration followed by a decrease. Suggest two reasons why the blood glucose concentrations decrease. Use information from to suggest which type of starch is healthier to have in the diet. Give a reason for your answer. Scientists want to produce a new wheat variety with an increased fibre content. Describe two methods they could use to do this.
4. Biological molecules  →  4.1. Biological molecules
18. Biotechnology and genetic modification  →  18.1. Biotechnology
8. Human nutrition  →  8.3. Absorption and assimilation
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3
is a photomicrograph showing part of a capillary network of a woman. The structure labelled X is a red blood cell. ×1250 W X Y Z The diameter of cell X in the photomicrograph is 10 mm. Calculate the actual diameter of cell X. Show your working and express your answer in micrometres (µm). actual diameter of cell X = W and X are both red blood cells. Explain why W and X appear different from each other in . Y and Z are both liquids. Name the liquids Y and Z and explain how liquid Z forms from liquid Y. Y Z explanation The woman has malaria and symptoms of anaemia. The malarial pathogens infect red blood cells where they multiply to form many new, genetically identical pathogen cells. These new pathogen cells burst out of the red blood cells. Describe how malarial pathogens can be transmitted from this woman to another person. Name the type of nuclear division that results in new pathogen cells. Suggest why infection with the malarial pathogen can cause anaemia. State one other cause of anaemia.
12. Disease and immunity  →  12.1. Disease
11. Transport in humans  →  11.4. Blood
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4
Some plants can survive extreme dehydration for a long time in a dormant state. They start growing again when water is available. They are adapted to survive in deserts. Selaginella lepidophylla is an example of this type of plant. shows a S. lepidophylla plant after several months without water and the same plant three days after rainfall. several months without water three days after rainfall plant is a brown colour plant is a green colour Explain how the changes in the plant, shown in , will help it to start growing again after rainfall. shows the cell wall and nucleus of a cell from this plant after several months without water. Suggest and explain the appearance of other parts of this cell after several months without water. You may draw on to help you answer. Selaginella lepidophylla is the scientific name for the plant species, which also has the common name ‘resurrection moss’. Explain what is meant by the term species. State the name of the scientific system used to name the species and suggest one advantage of using the scientific name rather than the common name. name of system advantage
3. Movement into and out of cells  →  3.1. Diffusion and osmosis
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5
Bacillus subtilis is a species of bacterium that is widely used in biotechnology. It can be used to manufacture the protein lipase for industrial use. is a diagram of B. subtilis. plasmid flagella D C B A Two of the parts labelled A, B, C and D in are involved in the manufacture of proteins such as lipase. Identify the two parts, name them and explain their role in protein manufacture. letter name role letter name role Suggest why B. subtilis has flagella. Explain why plasmids are useful in biotechnology. B. subtilis can be grown industrially in large containers. When B. subtilis is in ideal conditions it can reproduce rapidly, increasing the population size and the biomass of bacteria in the container. Graphs E and F in show how the biomass of B. subtilis increases after small populations of bacteria are added to two containers with different environmental conditions. 0.0 0.1 0.2 0.3 0.4 0.5 0.6 biomass of B. subtilis / g per dm3 time / hours F E Give the name of the large industrial containers used to grow bacteria. In graph E the biomass increases as shown in . Indicate using the letter M the part of graph E where bacteria are reproducing most rapidly. Calculate the percentage increase in biomass for graph E in the first 6 hours. Space for working. percentage increase in biomass = % Describe two differences between graph E and graph F. Suggest one environmental condition which could have caused the differences between graph E and graph F. Lipase is also produced by the human body. Explain why it is produced and how its function is different from the function of bile.
18. Biotechnology and genetic modification  →  18.1. Biotechnology
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6
A beam of bright light shines into a human eye for two seconds. A similar beam of light shines onto one side of the tip of a plant stem for several days. Describe the ways in which the human and the plant coordinate their responses to these beams of light. Your answer should include: • stimulus detection • method of responding. human plant Describe the role of synapses in a reflex arc.
14. Coordination and control  →  14.2. Mammalian sense organs
15. Coordination and response in plants  →  15.1. Coordination and response in plants
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