Chapter 34, Problem 12STP

Summary Introduction

To write:

The information about the autonomic and somatic nervous systems and lists the types of responses, systems affected, and examples.

Introduction:

The central nervous system and peripheral nervous system are the two major divisions of the nervous system. The spinal cord and the brain make up the CNS. The peripheral nervous system comprises the motor neurons and sensory neurons that carry information to and from the CNS. Neurons in the peripheral nervous system can be classified as either part of the somatic nervous system (SNS) or autonomic nervous system (ANS).

Explanation of Solution

Nerves in the SNS relay information from external sensory receptors to the CNS and motor nerves relay information from the CNS to skeletal muscles. This is voluntary. Some responses are the result of a reflex, which is a fast response to a change in the environment. Reflexes do not require conscious thought and are involuntary. Most signals in reflexes go only to the spinal cord and not to the brain.

Whereas the ANS carries impulses from the CNS to the heart and other inner organs. The body is responding involuntarily. ANS is important in two different conditions. If we have a bad nightmare, our body reacts to what is known as a fight-or-flight response. When everything is relaxed, our body will rest and digest. 

Conclusion

Thus, the ANS carries impulses from the CNS to the heart and other inner organs, and SNS relay information from external sensory receptors to the CNS.