The Nervous System

Gaiser Life Science

KnowWhat are the three functions of the nervous system?

Evidence

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The Nervous System

“I don’t know any.” is not an acceptable answer.Use complete sentences.

After listening to the PowerPoint lecture, come back here and list evidence to explain why your answer to the above question is or is not a good answer. You may also use other outside sources to help you respond.

Clarifying ?s Information

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Functions 1. Receives information - inside and outside the body2. Responds to info - reacts to stimulus (changes signal direction)

Nerve cells are stimulated by pressure, pain, or other input. The stimulation becomes a stimulus that travels down the nerve axon. The message jumps the synapse from the axon terminal of one nerve cell to the dendrite of another in electro-chemical form. The message may make this jump several times on the way to the central nervous system.

- another name for a nerve cell

Process3. Maintains homeostasis

The Nervous System

neuron

- messages that travel along the nervous systemimpulses

- branch-like structures located at the end of nerve cells, which receive electro-chemical messages from other nerve cells and carry the message to the nerve cell body or soma

dendrite

Clarifying ?s Information

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The Nervous System

Examples: grasp, patellar, gag, or pupillary light reflexes to mention only a few

Examples: running, opening a pop can, playing chess, or playing a piano

Process (continued)

The central nervous system receives the message for processing. The message can be processed in one of three ways:

- a long slender projection of a nerve cell that carries the impulse away from the cell body or soma

axon

1. In the case of a reflex, the message takes a short cut at the spinal column and goes back to the origin to trigger muscles.

2. Many messages go all the way to the brain to be consciously processed.

- the gap between the axon terminal of one nerve cell and the dendrite of another nerve cell

synapse

Clarifying ?s Information

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The Nervous System

Examples: Heart rate may increase. Breathing may become shallow. A muscle may activate an arm, leg, or hand. A gland may be stimulated to secrete a hormone. Organs can be stimulated to carry out their specific job.

Process (continued)

After the central nervous system determines how the message should be processed, a signal is sent back to the origin of the incoming signal. Again the message travels from one nerve cell to another. A variety of responses can then occur.

Examples: heart rate, respiration rate, salivation, perspiration, and others

3. Many responses of the body cannot be consciously controlled.

Clarifying ?s Information

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The Nervous System

Divisions of the nervous system

- This consists of the brain and spinal cord. It is the control center of the body. All muscles, organs, and glands are controlled from these locations.

Central nervous system

- these are the nerves that carry impulses from the central nervous system to all of the other locations of the body.

Peripheral nervous system

- a division of the peripheral nervous system that controls all voluntary actions.

Somatic nervous system Examples: running, singing, swimming, walking

- a division of the peripheral nervous system that controls all involuntary actions.

autonomic nervous system Examples: heart rate, perspiration, respiration

Summary:

Clarifying ?s InformationThe Nervous System

Functions 1. Receives information - inside and outside the body2. Responds to info - reacts to stimulus (changes signal direction)

Nerve cells are stimulated by pressure, pain, or other input. The stimulation becomes a stimulus that travels down the nerve axon. The message jumps the synapse from the axon terminal of one nerve cell to the dendrite of another in electro-chemical form. The message may make this jump several times on the way to the central nervous system.

- another name for a nerve cell

Process3. Maintains homeostasis

neuron

- messages that travel along the nervous systemimpulses

- branch-like structures located at the end of nerve cells, which receive electro-chemical messages from other nerve cells and carry the message to the nerve cell body or soma

dendrite

Process (continued)

The central nervous system receives the message for processing. The message can be processed in one of three ways:

- a long slender projection of a nerve cell that carries the impulse away from the cell body or soma

axon

- the gap between the axon terminal of one nerve cell and the dendrite of another nerve cell

synapse

Clarifying ?s InformationThe Nervous System

Examples: grasp, patellar, gag, or pupillary light reflexes to mention only a few

Examples: running, opening a pop can, playing chess, or playing a piano

1. In the case of a reflex, the message takes a short cut at the spinal column and goes back to the origin to trigger muscles.

2. Many messages go all the way to the brain to be consciously processed.

Examples: Heart rate may increase. Breathing may become shallow. A muscle may activate an arm, leg, or hand. A gland may be stimulated to secrete a hormone. Organs can be stimulated to carry out their specific job.

Process (continued)

After the central nervous system determines how the message should be processed, a signal is sent back to the origin of the incoming signal. Again the message travels from one nerve cell to another. A variety of responses can then occur.

Examples: heart rate, respiration rate, salivation, perspiration, and others

3. Many responses of the body cannot be consciously controlled.

Clarifying ?s Information

Summary:

The Nervous System

Divisions of the nervous system

- This consists of the brain and spinal cord. It is the control center of the body. All muscles, organs, and glands are controlled from these locations.

Central nervous system

- these are the nerves that carry impulses from the central nervous system to all of the other locations of the body.

Peripheral nervous system

- a division of the peripheral nervous system that controls all voluntary actions.

Somatic nervous system Examples: running, singing, swimming, walking

- a division of the peripheral nervous system that controls all involuntary actions.

autonomic nervous system Examples: heart rate, perspiration, respiration

This PowerPoint was created from Charlene Shea’s lecture notes by Tim This PowerPoint was created from Charlene Shea’s lecture notes by Tim Paterek. It is copyrighted and may not be reproduced outside the Paterek. It is copyrighted and may not be reproduced outside the

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