Module 1 The Nervous System

In This Module

Introduction

Module 1: The Nervous System Aids in Maintenance of the Status Quo

In this module you will explore both the conscious and unconscious communication of your body. You will do this through an examination of the structure, organization, and function of the nervous system. You will discover how the nervous system works to maintain homeostasis, and you will learn what occurs when communications are disrupted or interrupted. You will research how imbalances and disorders cause the nervous system to function improperly and how medical technologies can be applied to correct these situations.

 

As you progress through the course, you will be encouraged to use science and technology to acquire new knowledge and to solve problems. The scope and characteristics of science, its connections to technology, and the social context in which it is developed will be examined. You will be asked to critically address science-related societal, economic, ethical, and environmental issues.

 

Throughout this course you will find references to “The Key.” This is a Castle Rock Publication available for purchase from the Distance Learning Resources Branch, and from local book stores. This reference for Biology 30 includes multiple choice, numerical response and written response questions from past Diploma exams. You will find this a useful resource for review and studying. In addition to providing sample questions, an explanation of the marking rubrics used to grade the Diploma exam is also provided. It is an invaluable resource available to students preparing for the Diploma exam.

In This Module

 

Lesson 1: Structure and Organization of the Nervous System

When you were attracted to the new person in the room, you couldn’t control your breathing rate or your heart rate.  You withdrew your hand without thinking about it. The only thing you seemed to be able to control was walking across the room. But what would happen if you couldn’t even control the muscles moving your skeleton? Can technology help your body communicate with its’ various parts?

 

In this lesson you will investigate the following focusing questions:

• How is the nervous system organized and how do these parts communicate with each other?
• What interrupts the normal communication mechanisms of the sympathetic and parasympathetic parts of the nervous system?

Lesson 2:  The Brain and Spinal Cord—The Boss and Unthinking Boss

 

All information about your internal and external environment is transmitted to the brain and/or the spinal cord. The brain is the control centre for your body, just like the nucleus controls cell function. But if the spinal cord is damaged, then your brain can’t communicate successfully with your body. What are the implications? 

 

In this lesson you will investigate the following focusing questions:

• What are the main structures of the brain and spinal cord, what are their functions, and how do they coordinate those functions?
• What happens when the information to or from the brain or spinal cord is disrupted or interrupted?

Lesson 3:  The Basic Units of the Nervous System—The Neuron and the Reflex Arc

 

How embarrassing! You yanked your hand away from the very person you wanted to meet. How did something like that happen? You certainly didn’t plan it that way! Could this be like burning yourself on a hot stove? Why is your reaction so fast? Why do you become aware that the stove was hot only after you have moved your hand away from the source of heat?

 

This lesson helps you to understand the following focusing questions:

• What are the structures and functions of the neuron, and how do they support communication?
• What are the components of a reflex arc?

Lesson 4:  Sensory Perception—Taste, Smell, Touch, and Temperature Sensations

 

In the group of people that you approached, perhaps someone was eating pizza.  You could just taste it, even if all you could really do was smell it. Then there was the pain of the handshake, and you felt the room heat up. Or were you just embarrassed and getting hot and flustered? The nervous system responds to environmental stimuli. It does this through the senses.

 

The following focusing question will be addressed:

• What information about our environment do the sensations of touch, smell, and taste communicate to our nervous system in order to maintain homeostasis?

Lesson 5:  Photoreception—The Eye

 

Vision is our dominant sense. Do you wear contact lenses or glasses to help you see? If so, which parts of your eyes are not functioning well? Do we all see the same things?

The following focusing question will help you to understand the concept of photoreception:

• What are the major parts of the eye, how do they function and how do they communicate with the nervous system to support the integrated act of seeing?

Lesson 6:  Mechanoreception—The Ear

 

Your phone is ringing, but you can’t find it. No point asking your parents because they can’t hear it. Do we all hear the same things? Do other people in the room notice the laughter? Your heart starts to beat faster and you are breathing faster. Maybe you remember a time when this happened to you and you get dizzy. The ear also plays a role in establishing balance.

 

Understanding the following focusing questions will help you to learn about mechanoreception:

• What are the sturctures of the ear and what are their functions in communicating sound?

• How does the ear impact your ability to maintain balance within your changing environment?

Lesson 7: The Nerve Impulse—Transporting the Message

 

When you see the rotating dancer or you hear the mosquito ringtone, how are the image from the retina of the eye and the sound vibrations from the Organ of Corti communicated to the brain? Sometimes the messages are disrupted by disorders such as multiple sclerosis. What happens when communication is interrupted?

You will investigate the following question:

• How does the structure of a neuron facilitate the reception and transmission of a nerve impulse to the synaptic gap?

Lesson 8:  Synaptic and Neuromuscular Transmission—Crossing the Divide

 

Neurons are physically separated from each other by tiny gaps. The nerve impulse must be transmitted across this gap by chemicals called neurotransmitters. What might compromise synaptic transmission? Why does coffee excite your nervous system whereas alcohol inhibits it? How do anesthetics work so that you do not feel pain during surgery? Michael J. Fox and Mohammed Ali both have Parkinson’s disorder. How does this disorder interrupt synaptic communication?

 

To understand the concept of synaptic transmission you will investigate the following focusing questions:

• How do the anatomy and function of the synaptic gap and neuromuscular junction facilitate the transmission of nerve impulses between neurons, and between neurons and effectors?

• How do chemicals that we take into our body and disorders such as Parkinson’s Disease compromise synaptic transmission?