Biology 0610 · IGCSE · Diet

Diet — practice question

Carbohydrates form a major part of a balanced diet. Fig. 3.1 presents a flow chart showing several stages that carbohydrates in eaten food undergo. The boxes in Fig. 3.1 appear in this order: ingestion of large biological molecules; chemical digestion; absorption into the blood via the alimentary canal; increase in blood glucose concentration; assimilation in the liver.
(a)[8]

Using Fig. 3.1 as a guide, describe what happens to carbohydrates in the human body from ingestion until they are assimilated in the liver.

(b)[4]

State why calcium ions and iron ions are important in a balanced diet.

(c(i))[2]

List two factors, apart from diet and blood pressure, that the doctors used when judging the volunteers’ overall CHD risk.

(c(ii))[2]

Explain why urine tests are a reliable indicator of how much salt has been consumed.

(d(i))[1]

Suggest one other part of the diet of group 2, besides salt, that the doctors changed in order to lower the risk of developing CHD further.

(d(ii))[3]

Calculate the percentage increase in the group 1 volunteers’ average systolic blood pressure as their salt intake rose from low to high. low salt intake ............ kPa high salt intake ............ kPa Give your answer to the nearest whole number. Space for working.

(d(iii))[3]

The doctors concluded that certain diets lower the risk of CHD. Give evidence from Fig. 3.2 that supports this conclusion.

Worked solution & mark scheme

This 23-mark question has a full step-by-step worked solution and mark scheme. One marking point: ingestion / digestion takes place in the mouth

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