Question

What is in the correct order for general reflex arc?

Answer 1

Our body responds to the stimulus like heat, cold, pressure etc. This response does not involve the brain but the spinal cord. The response to the stimuli is called reflexes. This reflex undergoes the pathway which involves nerve cells. This pathway is called reflex arc.

Complete answer:
To answer this question, we must know about the components and pathway of the reflex arc.
The reflex arc is the path covered by the nerve impulses in a reflex called a reflex arc. The major components of the reflex system are-Receptor, Sensory neurons, control centre motor neurons, effector, response.

Let us discuss with a simple example of a stimulus that is hot surface and the path of response.
- The receptor cells are located on the skin which detects the stimuli that is the hot surface.
- The sensory neurons pick up the electrical impulse generated by the receptor and relays it to the control centre.
- The control centre is the spinal cord which process the electrical impulse and generate impulses.
- The impulse generated by the spinal cord is picked up by the motor neurons and transmitted to the effector.
- In this case the effector receives the impulse and brings about response that is muscle contraction for moving the hand away.

The reflex pathway is represented below-

So, we can clearly say that the path of reflex arc is receptor, sensory neurons, control centre, motor neurons and effector.

Note: In order to understand the reflex arc we should know the following terms-
i) Stimulus- It is referred to as physical or chemical change in the surrounding of an organism. This stimulus brings about a response.
ii) Reflex- It is an involuntary action that our body does in response to stimuli. It happens without thinking.
iii) Impulse- It is the electrical signal that travels in the nerve fibres and ends in the release of neurotransmitters by the brain or spinal cord.