Water, Carbohydrates and Lipids: Practice Questions

Many animals have a heart and a circulatory system. Which of the following best explains why a mass transport system is necessary for these organisms?

A clinical study evaluated the relationship between dietary fibre intake and the incidence of coronary heart disease (CHD). The researchers found that as fibre intake increased, the incidence of CHD decreased.

Which of the following is the most valid conclusion based on this finding?

Which of the following correctly describes the interaction between haemoglobin and carbon dioxide? <\/p>

In the blood clotting cascade, which ion is essential as a cofactor for the conversion of prothrombin to thrombin?

A sample of juice was tested using the DCPIP titration method to determine its vitamin C concentration. If it took 5.0 cm\(^3\) of a 0.1% vitamin C standard to decolourise 1.0 cm\(^3\) of DCPIP, and 8.0 cm\(^3\) of the juice sample to decolourise the same volume of DCPIP, what is the concentration of vitamin C in the juice sample?

State the specific disaccharide that is produced when two molecules of α-glucose are joined together by a 1,4-glycosidic bond.

Explain how the dipole nature of a water molecule allows it to effectively transport polar molecules, such as glucose, within the blood plasma.

A patient is diagnosed with an inherited disorder that leads to a deficiency in lipoprotein lipase, an enzyme responsible for breaking down triglycerides in the blood. Using your knowledge of ester bonds and lipid transport, explain how this deficiency would affect the concentration of triglycerides in the blood and why this might increase the risk of developing cardiovascular disease (CVD).

Water is a vital component of the blood and acts as an effective transport medium.

(a) Explain how the dipole nature of water molecules enables it to transport charged solutes such as sodium ions (\(Na^+\)) and chloride ions (\(Cl^-\)). (2 points)

(b) Small non-polar molecules like oxygen do not dissolve easily in water. State the name of the protein used to transport oxygen in the blood and explain how its structure is adapted for this function. (3 points)

Atherosclerosis is a condition that significantly increases the risk of cardiovascular disease (CVD).

(a) Describe the role of low-density lipoproteins (LDLs) in the development of atherosclerosis. (2 points)

(b) Explain how the formation of an atheroma can lead to a positive feedback loop that results in further damage to the artery wall and higher blood pressure. (3 points)