Module 1
1. Module 1
1.4. Page 2
Module 1—The Nervous System
Explore
Watch and Listen
central nervous system (CNS): the part of the nervous system that includes the brain and spinal cord
peripheral nervous system (PNS): the portion of the nervous system consisting of nerves and ganglia (collections of nerve cell bodies) that are outside the brain and spinal cord
neuron: the basic functional cell of the nervous system that is specialized to generate and transmit nerve impulses (messages)
nerve: a message pathway of the nervous system; made up of many neurons grouped into bundles and surrounded by protective tissue
There are 12 pairs of cranial nerves that insert into the brain and 31 pairs of spinal nerves that emanate from the spinal cord.
View the video “Electrochemical Control Systems in Humans: Regulating Physiological Processes.” You may be required to enter a username and password in order to access the video. Contact your teacher for this information.
As you watch the video, note the two divisions of the nervous system—the central nervous system, which is composed of the brain and the spinal cord, and the peripheral nervous system. Watch for the divisions of the peripheral system and how they control the body consciously and unconsciously. You may wish to prepare a flow chart or diagram to illustrate these relationships for later review.
The video also demonstrates communication and homeostasis. It explains the structures of the neuron, which is the basic building block of the nervous system, and outlines how neurons aid communication.
The organization of nerves to support communication is also detailed in this video. As you explore typical communication, keep in mind what could result when interruptions occur in the nervous system due to diseases like multiple sclerosis and Alzheimer’s disease.
You may choose to make rough, point-form notes as you watch the video. Such notes will be helpful in preparing your work in later lessons that deal specifically with these topics from the video. Your notes will also be useful in completing your assignment.
As you watch the video, pay specific attention to the following topics:
- the description and examples of homeostasis
- all the divisions of the nervous system and the examples of what each division does
- the neuron structure and its organization into nerves
- the biological basis of multiple sclerosis
Module 1: Lesson 1 Assignment
Retrieve the copy of the Module 1: Lesson 1 Assignment that you saved to your computer earlier in this lesson. Complete Part 1—Response to Video. Save your assignment in your course folder. You will receive instructions about when to submit your assignment to your teacher later in this lesson.
Read
The “Electrochemical Control Systems in Humans: Regulating Physiological Processes” video that you watched above provides a good introduction to the various parts of the nervous system and how they work. You may wish to read pages 366 to 369 and pages 396 to 399 in your textbook to increase your understanding. Based on your reading and the notes you made as you watched the video, make summary notes or a graphical organizer of this material to increase your understanding of the nervous system. Save your notes or graphical organizer in your course folder.
autonomic nervous system (ANS): a division of the peripheral nervous system that conducts nerve impulses to cardiac and smooth muscles, as well as to glands; may also be called the involuntary motor system
somatic nervous system (SNS): a division of the peripheral nervous system that conducts nerve messages to the skeletal muscles; may sometimes be called the voluntary nervous system
In both the video and the reading, the divisions of the nervous system, including the autonomic nervous system and the somatic nervous system, were shown to be vital to maintaining homeostasis.
The following Self-Check is an opportunity to practise your understanding of the autonomic and somatic nervous systems and how they communicate to maintain balance.
You can revisit the video or the reading if you need to review these systems.
Self-Check
SC 1. Complete the Comparing the Somatic and Autonomic Nervous System Self-Check.