B1.12b Skin senses

You do not need to remember the details of the skin receptors on this sheet for your exam but you could be asked to apply your knowledge to unfamiliar situations.

1 a What are the names of the two organs shown in the diagram?

b What system do these organs form?

The skin is the body’s largest sense organ, with an adult’s skin covering an area of about 1.8 m2 (the size of a shower curtain) and having a mass of between 3 and 5 kg. Although we think of the skin as being responsible for the sense of touch, it has many different sorts of receptor cells in it.

There are actually many different types of skin. The three main ones are:

● hairy – skin with hair!

● glabrous – skin without hair

● mucous membrane – skin that can produce sticky mucus.

The different types of skin have some or all of the receptor cells shown in the diagram.

2 a Your skin contains receptor cells for different stimuli. What is a stimulus?

b What is an organ that contains receptor cells called?

c Name one area of your body where you would expect to find many touch receptors. Explain your answer.

d You touch a cold stone. Which receptor cells would be activated?

e How does this information pass to the brain?

3 In glabrous skin, some receptors detect light pressure and others detect stronger pressure. Which of the receptors in the diagram do you think detect light pressure and which detect strong pressure? Explain your answers.

4 Meissner corpuscles are not found in hairy skin. Suggest why they are not needed.

Extra challenge5 a Name one area of your body where you would find mucous membrane.

b Name one receptor cell you would not expect to find in mucous membrane.

© Pearson Education 2010. Edexcel GCSE Science Activity PackThis document may have been altered from the original. 55