Chapter 15, Problem 1CP

How do the autonomic nervous system and somatic nervous system compare in structure and function?

Summary Introduction

To review:

The comparison between the structure and function of (somatic nervous system (SNS) and the autonomic nervous system (ANS).

Introduction:

The peripheral nervous system (PNS) consists of those neurons that exist outside the brain and spinal cord. It can be divided into two different parts, namely the ANS and SNS. The ANS involves no conscious control for its operation, in contrary with the SNS. The somatic nervous system voluntary controls body movements through skeletal muscles. However, the hypothalamus and brainstem does have a control over the reflexes of the ANS.

Explanation of Solution

The structural as well as the functional differences between the SNS and ANS are as follows:

S. no	SNS	ANS
1.	It is composed of the nerves that originates from the spinal cord.	It is composed of the nerves that originates from both the spinal cord as well as the brain.
2.	The nerves of the SNS help in the movement of the skeletal muscles.	The ANS supplies the internal structures and the visceral organs.
3.	The nerves have a continuous axon right from the spinal cord to the skeletal muscle.	The nerves have a discontinuous axon, which is separated by a ganglion.
4.	The continuous axon, then forming the neuromuscular junction is vital for the neural transmission.	Transmission is done through the release of the neurotransmitters in the synaptic area.

Conclusion

Thus, the SNS majorly controls the skeletal muscles, whereas the ANS is mostly involved in unconscious responses.