| Date | May 2013 | Marks available | 2 | Reference code | 13M.3.SL.TZ1.2 |
| Level | Standard level | Paper | Paper 3 | Time zone | Time zone 1 |
| Command term | Evaluate | Question number | 2 | Adapted from | N/A |
Question
The following are from the labels of a bag of all purpose white flour (wheat) and a bag of parboil long grain rice. Amounts shown are per serving.
Using your knowledge of the energy content of nutrients, calculate the protein energy value of a serving of rice, showing the units.
Compare wheat flour and rice as main dietary sources of energy for humans.
Evaluate the benefits of reducing dietary cholesterol in lowering the risk of coronary heart disease.
Markscheme
a. energy value of 100 g protein ≈ 1720 kJ / energy value of protein ≈17 kJ/g;
b. 2g protein
energy value / ECF kJ of 100g protein
34.4 kJ/ECF kJ value;
100g protein
Answer range 34–35 kJ/ECF kJ.
For calculation note error carried forward.
Units required. If no units deduct a mark and indicate in scoris U –1.
a. wheat and rice almost equivalent for energy value;
b. rice has only slightly less kJ/energy from fat/protein / more from carbohydrate;
c. considering food miles / availability may be decision factor for choice;
a. dietary cholesterol correlated to blood cholesterol/fatty acids;
b. high blood cholesterol is an important risk factor (but not the only cause);
c. some cholesterol required for normal synthesis of body molecules;
d. genetic factors play an important role in determining cholesterol levels;
e. other environmental factors (smoking) play a role in determining cholesterol levels;
Examiners report
In A2 (b) the majority of candidates could perform the required calculation.
Few were able to appropriately compare wheat flour and rice as sources of energy.
In A2 (c) many candidates gave very long answers talking about the benefits of reducing cholesterol but did not connect them to heart disease.
