Receptors are present in all parts of our body, for example, in the skin, eyes, nose, tongue, etc. A receptor is a cell (or a group of cells) in a sense organ which is sensitive to a paritcular type of stimulus such as light, sound, smell, taste, heat, pressure, etc.
The different sense, organs contain receptores for detecting different stimuli.
The eyes have light receptors called photoreceptors (which can detect light).
Ears have sound receptors called phonoreceptors (which can detect the sounds).
The nose has smell receptors called olfactory receptors which can detect the smell.
Tongue has taste receptors which are called gustatory receptors which detect taste.
Skin has receptors called thermoreceptors which detect touch, pressure.
When receptors do not work properly, the environmental stimuli are not able to create nerve impluses and the body does not respond. When receptors are damaged, the external stimuli transferring signals to the brain are not felt.
For Example,
- during fever, taste buds do not work properly and as a result, taste of the food eaten is not felt properly thus enzyme secretion is also affected.
- when a person is suffering fom a cold, the nostrils are filled with mucus. Then smell of the surrounding is not felt properly. This is due to interruption in reacting to the sense of smell by the olfactory receptor.
- when skin receptors are damaged, and we accidentally touch a hot object, then our hands might get burnt as the damaged receptor cannot perceive the external stimuli of heat and pain.
