5090_w18_qp_22
A paper of Biology, 5090
Questions:
9
Year:
2018
Paper:
2
Variant:
2
Login to start this paper & get access to powerful tools
1
Fig. 1 and Fig. 2 show transverse sections of two types of blood vessel. Fig. 1 Fig. 2 Name the type of blood vessel shown in: Fig. 1 Fig. 2 Describe the differences in the structures shown in Fig. 1 and Fig. 2 that helped you to identify these blood vessels. The diagram below is of a simplified, incomplete longitudinal section from the type of blood vessel shown in Fig. 2. The direction of blood flow is shown. direction of blood flow Complete the diagram by drawing one set of valves. Describe the function of these valves.
11. Transport in humans  →  11.3. Blood vessels
11. Transport in humans  →  11.1. Circulatory system
Open
2
The diagram shows the human male reproductive organs and associated structures. fluid from organ G tube H tube E organ F Identify each of the following: tube E organ F organ G tube H State one difference between the fluids carried by tube E and tube H. State one way in which the fluid from organ G may be different in a person with diabetes compared to a person without diabetes. A person with diabetes may be treated with insulin produced by genetically modified bacteria. Outline how such genetically modified bacteria may be produced and used to manufacture human insulin on a commercial scale.
16. Development of organisms and continuity of life  →  16.4. Sexual reproduction in humans
Open
3
The diagram shows a pollen grain with a pollen tube growing from it. Pollen grains from the same type of plant were placed in sucrose solutions of different concentrations for a fixed amount of time. After this time, the pollen grains and tubes were examined using a microscope. The following observations were made for each concentration of sucrose: • the number of pollen grains that had germinated to produce a pollen tube, • the length of each pollen tube. The table shows the results of the investigation. % sucrose concentration % of pollen grains germinated mean pollen tube length / mm 0.005 0.008 0.015 0.040 0.030 0.018 0.006 A total of 12 pollen grains were placed in the 20% sucrose solution. Use the information in the table to calculate the number of pollen grains that germinated to produce a pollen tube in the 20% sucrose solution. Suggest why the mean pollen tube length was calculated for each sucrose concentration. Use the information in the table to suggest the optimum concentration of sucrose solution for pollen tube germination and growth. % Explain how the information in the table enabled you to reach this conclusion. The germination of a pollen grain to form a pollen tube requires the movement of water into the pollen grain from its surroundings. Suggest why placing a pollen grain in a solution with a higher sucrose concentration than in your answer to may result in a lower percentage of germination. Describe the route taken by a growing pollen tube in a plant and explain its importance in plant reproduction.
16. Development of organisms and continuity of life  →  16.3. Sexual reproduction in plants
Open
4
The graph shows the variation in the concentration of dissolved carbon dioxide in the water of a pond over a period of 24 hours. night night day carbon dioxide concentration of gas time Explain how plants that live in the water contribute to the changes in concentration of dissolved carbon dioxide shown in the graph. Draw a line on the graph above to show how the concentration of dissolved oxygen in the water of the same pond is likely to change over the same period of time. Carbon dioxide dissolves in water to form an acidic solution. The higher the concentration of dissolved carbon dioxide, the lower the pH. Ammonia is a toxic chemical found in ponds, that may harm fish. The graph shows how the concentration of dissolved ammonia in the water of a pond changes as the pH changes. pH % ammonia Use this graph and the graph on page 8 to suggest and explain at which time of day fish that live in the pond are most likely to be affected by the toxic effects of ammonia. Draw a ring around the correct time of day. time of day sunrise midday sunset explanation
6. Plant nutrition  →  6.1. Photosynthesis
19. Relationships of organisms with one another and with the environment  →  19.4. Effects of humans on ecosystems
Open
5
Describe the role of each of the following hormones in the menstrual cycle: FSH, progesterone. The chart shows the timing and duration of events that take place during part of a menstrual cycle. ovulation menstruation key: fertile phase day in cycle event in cycle phase of cycle 9 10 11 12 13 14 15 16 17 18 Suggest why pregnancy may occur if sexual intercourse takes place several days before ovulation. Name the method of birth control that makes use of the information in a chart like this. Explain how this method of birth control is used to prevent pregnancy. name of method explanation Suggest why the method of birth control that you have named in is considered to be unreliable.
16. Development of organisms and continuity of life  →  16.4. Sexual reproduction in humans
Open
6
The graph shows how the percentage of carbon dioxide in the atmosphere has changed since the year 1700. 1700 1750 1800 1850 1900 year 1950 2000 2050 0.038 0.040 0.036 0.034 % carbon dioxide 0.032 0.030 0.028 Explain how human activity is likely to have contributed to the change in the percentage of carbon dioxide. Describe and evaluate the effects of this change in the percentage of carbon dioxide.
6. Plant nutrition  →  6.1. Photosynthesis
19. Relationships of organisms with one another and with the environment  →  19.4. Effects of humans on ecosystems
Open
7
Fig. 1 shows a leaf immediately after falling from a growing plant. Fig. 2 shows a leaf from the same plant several months after falling from the plant onto the soil below. Fig. 1 Fig. 2 Name the process that has taken place to cause the leaf in Fig. 2 to appear different from that in Fig. 1. Explain how named types of microorganism have carried out this process. Explain how the plant benefits from this process taking place in the large number of leaves that fall from the plant onto the soil below.
3. Movement into and out of cells  →  3.1. Diffusion and osmosis
6. Plant nutrition  →  6.2. Leaf structure
Open