0610_w19_qp_43
A paper of Biology, 0610
Questions:
6
Year:
2019
Paper:
4
Variant:
3

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Plants produce glucose in leaves and convert some of it to sucrose. Explain how glucose is produced in leaves. State the name of the process that plants use to move sucrose from a source to a sink. Roots can be an example of a sink. Explain why sometimes roots act as a source rather than a sink. The movement of sucrose in plants can be modelled using laboratory apparatus. shows the apparatus used to model the movement of sucrose in a plant: • Partially permeable bags were attached tightly to the ends of tube Q. • The bag representing a source was filled with a coloured sucrose solution. • The bag representing a sink was filled with water. • The containers and tube Q and tube S were filled with water. bag representing a source containing a coloured sucrose solution partially permeable membrane P water tube Q bag representing a sink containing water partially permeable membrane R tube S shows the position of the coloured sucrose solution 30 minutes after the apparatus was set up. The arrows show the direction of the movement of the liquids. bag representing a source partially permeable membrane P water tube Q movement of sucrose solution movement of water bag representing a sink partially permeable membrane R tube S State the name of the tissue represented by tube Q and the name of the tissue represented by tube S in . Q S Explain why the sucrose solution moves along tube Q in the model in . In plants the movement of sucrose is usually continuous. However, after 2 hours the movement of sucrose in tube Q in stopped. Suggest why the movement of sucrose in tube Q stopped. Amino acids are also transported through plants. State the name of the mineral ion that is used to make amino acids.
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Carbohydrates are an important component of a balanced diet. The flow chart in shows some of the processes that happen to carbohydrates in food that is eaten. ingestion of large biological molecules chemical digestion absorption into the blood via the alimentary canal increase in blood glucose concentration assimilation in the liver Describe what happens to carbohydrates in the human body between ingestion and assimilation in the liver. Use the information in as a guide. Mineral salts are another important component of a balanced diet. State the importance of calcium ions and iron ions in a balanced diet. calcium ions iron ions Consuming too much of some mineral salts, such as sodium chloride, increases the risk of developing coronary heart disease (CHD). Doctors studied the effect of diet on the risk of developing CHD. The doctors first selected volunteers who had a high salt diet. The doctors assessed the volunteers’ overall risk of developing CHD and monitored their blood pressure. List two factors, other than diet and blood pressure, that the doctors considered when assessing the overall risk of the volunteers developing CHD. The doctors used urine tests to identify volunteers who had a high salt diet. Explain why urine tests are a good indicator of how much salt has been consumed. The volunteers were divided into two groups. The mass of salt consumed by both groups was changed every 4 weeks: • low salt intake for 4 weeks • medium salt intake for 4 weeks • high salt intake for 4 weeks. In addition, group 2 was given other changes to their diet but group 1 was not. Suggest one component of the diet of group 2, other than salt, that the doctors changed to further reduce the risk of developing CHD. The systolic blood pressure of the volunteers was measured every 4 weeks. These results are shown in . 15.0 15.5 16.0 16.5 17.0 17.5 18.0 average systolic blood pressure / kPa low medium salt intake high group 1 Key: group 2 Calculate the percentage increase in the average systolic blood pressure of the group 1 volunteers when they increased their salt intake from low to high. low salt intake kPa high salt intake kPa Give your answer to the nearest whole number. Space for working. % The doctors concluded that some diets reduce the risk of CHD. Give evidence from to support this conclusion.
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