List two dietary sources of vitamin D.

State an example of these receptors in humans.

Discuss exposure to sunlight as a source of vitamin D.

e.g. cod liver oil / fish liver oil / oily fish (accept correctly named example) / egg yolk / fortified cereal / ONE named dairy product (i.e. milk/cheese/ yoghurt)
Allow any two sources for the mark. Reject fish alone.

hair cells of cochlea

UV light/sunlight on skin causes chemical production of vitamin D;
UV too low in winter in high latitudes;
vitamin D stored in liver so can make enough to last several months/through winter;
UV light can damage skin and cause skin cancer so exposure needs to be limited;
use of sun-block will inhibit vitamin D production;
covering skin with clothing prevents UV reaching skin; Accept reference to cultural/religious customs

Many gained the mark here, but a large proportion could not list two valid dietary sources of vitamin D, often giving fruit and vegetables as a possibility. The emphasis should also have been on oily fish.

Few correct answers to this part, many suggesting “eardrum”, or simply “hairs in ears”.  

This question was badly answered on the whole. The main misconception is that sunlight contains vitamin D, and many did not explain the role of the skin in the production of the vitamin. There is, however, an overall general awareness of the connection between UV light and skin cancer