0610_w15_qp_33
A paper of Biology, 0610
Questions:
6
Year:
2015
Paper:
3
Variant:
3
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1
shows seven marsupial mammals. A B C D E F G not drawn to scale State one visible feature that could be used to identify the marsupials in as mammals. Use the key to identify each species. Write the letter of each species (A to G) in the correct box beside the key. One has been done for you. key 1 tail visible go to 2 no tail visible go to 3 2 back feet at least twice as long as front feet go to 4 back feet and front feet of similar length go to 5 3 large ears relative to the size of the head Phascolarctos cinereus small ears relative to the size of the head Vombatus ursinus 4 tail at least twice as long as body Sminthopsis longicaudata tail less than twice as long as body Macropus rufus 5 uniform body colouring Paljara tirarense markings on body go to 6 6 white band across back and chest Sarcophilus harrisii no white band across back and chest Dasyurus maculatus G Sexual reproduction occurs in all mammals. A zygote is formed from the fertilisation of a male gamete and a female gamete. Name the process that results in the formation of haploid gametes. Explain the importance of sexual reproduction in mammals. Marsupials differ from other mammals by giving birth to relatively undeveloped offspring. Female humans have a placenta and therefore give birth to more developed offspring. Describe the role of the placenta in humans. In humans, the placenta is connected to the amniotic sac which contains amniotic fluid. State two functions of the amniotic fluid.
16. Reproduction  →  16.4. Sexual reproduction in humans
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2
shows a diagram of the liver and the blood vessels that enter and exit from it. to the heart from the heart small intestine liver J K L M Name blood vessel L. Blood vessel J is a vein. State two structural features of veins and explain how each feature is related to its function of returning blood to the heart. feature explanation feature explanation Blood samples were taken from each of the blood vessels J, K, L and M two hours after a meal of rice. Table 2.1 shows the concentration of glucose in these blood samples. Table 2.1 blood vessel blood glucose concentration / mg per 100 cm3 J K L M Calculate the percentage increase in blood glucose concentration between blood vessel J compared with L. Express your answer to the nearest whole number. Show your working. % Control of blood glucose by the liver is an example of homeostasis. Explain how the liver lowers blood glucose concentration when it is too high. Name one other factor in the human body that is also controlled by homeostasis. Amino acids are processed by the liver. Describe this process. State one other function of the liver, besides homeostasis and processing amino acids.
14. Coordination and response  →  14.4. Homeostasis
9. Transport in animals  →  9.4. Blood
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3
Researchers designed an investigation to find the effect of increasing levels of exercise on two groups of people. The first group of people were trained cyclists and the second group were untrained cyclists. The researchers asked all the people to cycle at four levels of effort: 30%, 45%, 60% and 75% of their maximum cycle speed. They cycled for eight minutes at each level of effort. The researchers predicted that the pulse rate of all the cyclists would increase during exercise. Explain this prediction. shows the average concentration of lactic acid in the blood of the trained cyclists and untrained cyclists in the investigation. average lactic acid concentration / arbitrary units untrained cyclists trained cyclists time / minutes key level of effort 30% 45% 60% 75% after exercise Describe the effect of the increasing levels of effort on the average lactic acid concentration in the blood of the untrained cyclists. You should use data from in your answer. Lactic acid is produced in the muscles during anaerobic respiration. Define the term anaerobic respiration. Describe how the lactic acid produced in muscle cells enters the blood. Name the component of the blood that transports lactic acid. Explain why the lactic acid concentration in the blood in trained cyclists is different from the untrained cyclists eight minutes after the exercise. You should use data from in your answer.
12. Respiration  →  12.3. Anaerobic respiration
11. Gas exchange in humans  →  11.1. Gas exchange in humans
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4
Water moves into plants from the soil and exits through the leaves. Explain how water moves from the soil into the root. Water reaches the leaves from the roots through the xylem. shows images of stomata on the lower surfaces of leaves of two varieties of olive plant, A and B. Both are shown at the same magnification. A B Describe the function of stomata. Compare the density of stomata between the two varieties of olive plant, A and B, shown in . Under identical environmental conditions the rate of water uptake in plant A is higher than plant B. Explain why. The density of stomata is an example of a leaf adaptation to the environmental conditions. State two other adaptations of leaves for survival in a dry environment. Water lost from the leaves enters the atmosphere. Describe how water is recycled from the atmosphere back to the roots.
3. Movement into and out of cells  →  3.2. Osmosis
8. Transport in plants  →  8.3. Transpiration
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5
Plastic bags cause many problems in the environment. Plastic bags were banned in Bangladesh in 2002. Outline the effects of non-biodegradable plastics on the environment. Some countries have not banned plastic bags. There have been many studies to analyse possible alternatives to plastic bags. Table 5.1 shows the results of a study comparing the environmental impact of producing plastic bags and paper bags. Table 5.1 environmental impact of production plastic bags paper bags waterborne chemical waste / g per bag 1.1 2.7 airborne chemical waste / g per bag 0.025 1.25 energy used / kJ per bag trees used per bag 0.0014 oil used / dm3 per bag 0.022 Compare the environmental impact of making plastic bags with the environmental impact of making paper bags. You should use data from Table 5.1 in your answer. Heavy metals and acids are the most common waterborne chemical wastes from the production of paper bags. Describe the effects of these waterborne chemical wastes on the environment. Table 5.2 shows the results from a study comparing recycling of plastic bags and paper bags. Table 5.2 plastic bags paper bags bags recycled / % 0.6 19.4 energy used to recycle / kJ per bag 14 444 Compare the energy used to make plastic bags with the energy used to recycle plastic bags. You should use data from Table 5.1 and Table 5.2 in your answer. Pollution by heavy metals and acid is one concern about the making of paper bags. There are additional concerns about the making and recycling of paper bags. Discuss these additional concerns.
20. Human influences on ecosystems  →  20.3. Pollution
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6
Define the term genetic engineering. is a flow diagram that shows how insulin can be produced using genetic engineering. R Q L M N O P Table 6.1 shows stages in the production of insulin by genetic engineering. Complete Table 6.1. The first row has been done for you. Table 6.1 letter from name description M chromosomes threads of DNA found in the nucleus section of DNA removed from human cell plasmid type of cell that is genetically engineered specific chain of amino acids coded by the section of DNA removed from the human cell fermenter The genetically engineered cells in reproduce asexually. Explain the advantages of asexual reproduction for insulin production by genetic engineering.
21. Biotechnology and genetic modification  →  21.3. Genetic modification
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