Ask a Teacher

Search



If we touch a hot object by our head does the impulse go to spinal cord or straight away to our brain?explain?
A reflex action is an automatic response to a stimulus.

An example of the way in which we respond to a stimulus is our reaction to touching a hot object (like a hot plate). The stimulus here is the heat which we feel in our hand on touching the hot plate. This heat is sensed by a heat receptor (or thermoreceptor) in our hand. The receptor triggers an impulse in a sensory neuron, which transmits the message to the spinal cord.

Here, the impulse is passed on to a relay neuron, which in turn, passes it to a motor neuron. The motor neuron passes the impulse to a muscle in our arm. The muscle then contracts and pulls our hand away from the hot plate. The muscle of arm  are effectors because it responds to the stimulus. This pathway along which the impulse travels is called the reflex arc.

The reflexes of this type which involve only the spinal cord are called spinal reflexes. Though spinal reflexes are produced in the spinal cord but the message of reflex action taken also  reaches the brain.


comments powered by Disqus