DO NOW PG 69

1. THE CENTRAL NERVOUS SYSTEM IS LOCATED WITHIN

WHICH 2 BODY STRUCTURES?

2. LIST ONE FUNCTION OF THE NERVOUS SYSTEM

ANATOMY AND PHYSIOLOGY OF THE CENTRAL AND PERIPHERAL NERVOUS

SYSTEMS

NEUROFIBRILS

• A network of fine threads within the

cell body or a neuron

CHROMATOPHILIC SUBSTANCE

• Membranous sacs spread

throughout the cytoplasm or a

neuron cell body

MYELIN SHEATHS

• These cells wrap tightly around

axons, like a band-aid, coating

them with many layers of cell

membrane that have little or no

cytoplasm between them.

NEURILEMMA

• A sheath, containing mostly

cytoplasm and the nuclei, that

surrounds the myelin sheath

NODES OF RANVIER

• Narrow gaps between schwann

cells

CLASSIFICATION OF NEURONS

Structural differences:

• Multipolar neurons

• Bipolar neurons

• Unipolar neurons

Functional differences:

• Sensory Neurons

• Interneurons

• Motor Neurons

MULTIPOLAR NEURONS

• Only one process of each neuron is

an axon; the rest are dendrites

• Most neurons whose cell bodies lie

within the CNS are multipolar

BIPOLAR NEURONS

• 2 process; one is a an axon and

the other a dendrite

• Neurons located in specialized parts

of the eyes, nose, and ears are

bipolar

UNIPOLAR NEURONS

• One function as a single axon

• Ganglia: the cell bodies of some

unipolar neurons that aggregate in

specialized masses of nerve tissue

SENSORY NEURONS

• Carry nerve impulses from

peripheral body parts into the brain

or spinal cord

INTERNEURONS

• Lie entirely within the brain or spinal

cord

• Transmit impulses from one part of

the brain or spinal cord to the other

• Nuclei: The cell bodies of

interneurons that aggregate in

specialized masses of nervous tissue

MOTOR NEURONS

• Multipolar, carry nerve impulses out

of the brain or spinal cord to

effectors.

• Stimulate muscles to contract and

glands to release secretions

LAB ACTIVITY – SENSORY RECEPTORS

• In small groups of 2-5

• Complete lab activity

• Answer lab questions

• When Finished:

• Go back to your seat

• Begin working on nervous system

worksheet

• You may use your notes and the book