Sensory receptor
is a mechanism of the living organisms, in which through the sensory receptors,
they have the ability to respond to both external and internal environment changes.
Animals use their senses to avoid enemies and to suit their living environment.
Dogs have a very sensitive nose, which is very useful for them to fetch for food
and other things. Therefore, if a living thing has one or two sharp and sensitive
senses, it is given a decided survival advantage. On the other hand, plants use
their sensory receptors to situate the sources of light and to support themselves
with gravity.
A sensory receptor,
or sense cell, is a particular structure of the sensory nerve in which it is
excited by a certain stimulus. There are different kinds of stimulus, which can
excite the sense cell. It may be photoreceptive (light), thermal (heat or cold)
or chemical (taste). External receptors allow one to assess the environment then
it can give the best reaction. Internal receptors monitor the physical and chemical
states of the body. When there is information collected through the sensory receptors,
it will then be processed and interpreted by the central nervous system. Once
I have touched something very hot - the receptor is motivated, a message called
a nerve impulse will quickly transfer over a nerve fiber to the particular place
in the brain where identify sensations, such as touch or smell, are interpreted;
as a result, I will feel the hotness and take responds - take away my hands.
