Chapter 3, Problem 1PT

Summary Introduction

Introduction:

The nervous system is a complex network of nerve cells. Nerves are the basic unit of the nervous system. The nervous system is classified into two major divisions’ central nervous system and peripheral nervous system. The peripheral nervous system is subdivided into a sensory division (afferent) and motor division (efferent).

Answer to Problem 1PT

Correct answer:

Sensory neurons are responsible for detecting the information from the environment and pass it to the brain. Therefore, option (b) is correct.

Option (b) is given as “sensory neuron”.

Explanation of Solution

Justify the reasons for the correct statement:

Sensory neurons are the nerve cells which are responsible for external stimuli from the environment into electrical impulses. Afferent or sensory neurons conduct signal towards the CNS in response to stimuli such as heat, light, etc.

Hence, option (b) is correct.

Justify the reasons for the incorrect statements:

Option (a) is given as “motor neuron”.

Efferent or motor neurons send a signal to the gland cells and the muscle cells. The signal from the CNS is carried to muscles and glands by motor neurons. Hence, it is a wrong answer.

Option (c) is given as “interneuron”

The neurons, which receives, process and store information in response to stimuli are known as interneurons. The interneurons carry out integrative functions of the nervous system. These neurons are useful in making decisions which constitute about 90% of the nervous system. Hence, it is a wrong answer.

Option (d) is given as “glia”

Glial cells are the surrounding cells of the nerve cells. They are not involved in sending signals to the brain. Hence, it is a wrong answer.

Hence, options (a), (c), and (d) are incorrect.

Conclusion

The stimuli from the environment are sent to the CNS by the afferent neurons.