- Our skin is sensory organ that can detect stimuli such as pain, pressure, touch, heat and cold.
- Our skin consists of two main layers: Epidermis (outer layer) and Dermis (inner layer)
- There are 5 types of receptors in our skin. Can you identify them in the figure above?
- Each type of receptor is sensitive to a different stimulus.
- The skin at different body parts is not equally sensitive to stimuli. The skin of some body parts is more sensitive than that of other body part.
- Such difference is due to the different thickness of the epidermis and different numbers of receptors in the skin.
Watch the following video: Skin sensitivity
After watching the video, can you identify which parts of our body part have great sensitivity and less sensitivity?
How sensitive are you? Try out this simple experiment.
What did you find?
On some parts of the body, such as the index finger is more sensitive. This means that the volunteer has more sensory receptors in that part of their body. Sensory receptors are specialised cells. They detect changes in the environment, called stimuli, and turn them into electrical impulses. In this case, the sensory receptors are detecting pressure. Sensory neurones - nerve cells - carry these electrical impulses to the spinal cord and brain.To be really sensitive, each sensory receptor must connect to a different nerve cell.
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