Nervous System

You are driving down the freeway, and a horn blares on your right. You swerve to your left. Charlie leaves a note on the kitchen table: "See you later-have the stuff ready at 6." You know that the "stuff" is chili with taco chips. You are dozing, and your infant son makes a soft cry. Instantly, you awaken. What do all these events have in common? They are all everyday examples of the functioning of your nervous system, which has your body cells humming with activity nearly all the time.

The nervous system is the master controlling and communicating system of the body. Every thought, action, and emotion reflects its activity. Its signaling device, or means of communicating with body cells, is electrical impulses, which are rapid and specific and cause almost immediate responses.
Objective Checklist

Organization of the Nervous System

• List the general functions of the nervous system.
• Explain the structural and functional classifications of the nervous system.
• Define central nervous system and peripheral nervous system and list the major parts of each.

Nervous Tissue: Structure and Function

• State the function of neurons and neuroglia.
• Describe the general structure of a neuron and name its important anatomical regions.
• Describe the composition of gray matter and white matter.
• List the two major functional properties of neurons.
• Classify neurons according to structure and function.
• List the types of general sensory receptors and describe their functions.
• Describe the events that lead to the generation of a nerve impulse and its conduction from one neuron to another.
• Define reflex arc and list its elements.

Central Nervous System

• Identify and indicate the functions of the major regions of the cerebral hemispheres, diencephalon, brain stem, and cerebellum on a human brain model or diagram.
• Name the three meningeal layers and state their functions.
• Discuss the formation and function of cerebrospinal fluid and the blood-brain barrier.
• Compare the signs of a CVA with those of Alzheimer's disease; of a contusion with those of a concussion.
• Define EEG and explain how it evaluates neural functioning.
• List two important functions of the spinal cord.
• Describe spinal cord structure.

Peripheral Nervous System

• Describe the general structure of a nerve.
• Identify the cranial nerves by number and by name, and list the major functions of each.
• Describe the origin and fiber composition of (a) ventral and dorsal roots, (b) the spinal nerve proper, and (c) ventral and dorsal rami.
• Discuss the distribution of the dorsal and ventral rami of spinal nerves.
• Name the four major nerve plexuses, give the major nerves of each, and describe their distribution.
• Identify the site of origin and explain the function of the sympathetic and parasympathetic divisions of the autonomic nervous system.
• Contrast the effect of the parasympathetic and sympathetic divisions on the following organs: heart, lungs, digestive system, blood vessels.

Developmental Aspects of the Nervous System

• List several factors that may have harmful effects on brain development.
• Briefly describe the cause, signs, and consequences of the following congenital disorders: spina bifida, anencephaly, cerebral palsy.
• Explain the decline in brain size and weight that occurs with age.
• Define senility and list some possible causes.