1. A patient with type 2 diabetes has been advised to follow

a low-carbohydrate diet. Explain how this diet can help to

control the blood glucose level of the patient. (4 marks)

Answer: A low-carbohydrate diet can help to control the

blood glucose level of the patient by reducing the intake of

glucose from food sources. This can lower the demand for

insulin, which is the hormone that regulates the uptake of

glucose into cells. Insulin resistance is a common feature of

type 2 diabetes, which means that the cells do not respond

well to insulin and do not take up enough glucose from the

blood. By reducing the glucose intake, the patient can

avoid high blood glucose levels that can cause

complications such as nerve damage, kidney damage and

cardiovascular disease. (4 marks)

2. A researcher is investigating the effect of different types

of lipids on the membrane fluidity of red blood cells. She

extracts the lipids from the membranes of red blood cells

and separates them by thin-layer chromatography (TLC).

She then measures the distance travelled by each lipid on

the TLC plate and calculates the Rf value for each lipid.

The Rf value is the ratio of the distance travelled by the

lipid to the distance travelled by the solvent. She obtains

the following results: