1. Chapter 7 The Nervous System
Essentials of Human Anatomy & Physiology
Seventh Edition
Elaine N. Marieb
Chapter 7 The Nervous System
Slides 7.1 – 7.22
Lecture Slides in PowerPoint by Jerry L. Cook
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

2. Human A&P Warm Up What is the purpose of the nervous system?
Identify some of the nervous systems anatomical parts.

3. Objective
We will….discuss the purpose of the nervous system and the anatomical make up of the nervous system.

4. Agenda
The Demon in the Freezer book study is due tomorrow

5. Functions of the Nervous System
Sensory input – gathering information
To monitor changes occurring inside and outside the body
Changes = stimuli
Integration
To process and interpret sensory input and decide if action is needed
Slide 7.1a
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6. Functions of the Nervous System
Motor output
A response to integrated stimuli
The response activates muscles or glands
Slide 7.1b
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7. Structural Classification of the Nervous System
Central nervous system (CNS)
Brain
Spinal cord
Peripheral nervous system (PNS)
Nerve outside the brain and spinal cord
Slide 7.2
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8. Partner Discussion Question 1: Question 2: Question 3:
What classification of the nervous system is responsible for sensory input? Explain.
Question 2:
What classification of the nervous system is responsible for integration? Explain.
Question 3:
What classification of the nervous system is responsible for motor output? Explain.

9. Functional Classification of the Peripheral Nervous System
Sensory (afferent) division
Nerve fibers that carry information to the central nervous system
Figure 7.1
Slide 7.3a
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10. Functional Classification of the Peripheral Nervous System
Motor (efferent) division
Nerve fibers that carry impulses away from the central nervous system
Figure 7.1
Slide 7.3b
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

11. Functional Classification of the Peripheral Nervous System
Motor (efferent) division
Two subdivisions
Somatic nervous system = voluntary
Autonomic nervous system = involuntary
Figure 7.1
Slide 7.3c
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12. Organization of the Nervous System
Figure 7.2
Slide 7.4
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13. Nervous System Activity
Groups of 3
Supplies
Meterstick
Purpose : The purpose of this activity is to evaluate how the nervous works.
1st trial
Concentrate on the meterstick and catch it between thumb and 1st digit when dropped
Repeat this three times writing down results
2nd trial
Repeat the steps of the first trial with distractions

14. Hypothesis
If testing how the nervous system functions with and without distractions then …..

15. Data Centimeters Trial #1 – No Distractions Trial #2 – No Distractions
Trial #1 – With Distractions
Trial #2 – With Distractions
Trial #3 – With Distractions

16. Conclusion
Explain if your hypothesis was correct using your data to support your findings.
When applying this knowledge to things like driving what does your data suggest?

17. Closure
I will….write on an exit card two things that I learned about the nervous system today and one thing that I still have a question about.

18. Human A&P Warm Up
Create a diagram that represents the divisions of the nervous system.

19. Objective
We will….discuss the support cells of the nervous system and the neuron.

20. Agenda Turn in The Demon in the Freezer book study Career Survey Notes
Diagram
The Demon in the Freezer Book…extra credit for daily grade if donated

21. Nervous Tissue: Support Cells (Neuroglia)
Astrocytes
Abundant, star-shaped cells
Brace neurons
Form barrier between capillaries and neurons
Control the chemical environment of the brain
Figure 7.3a
Slide 7.5
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22. Nervous Tissue: Support Cells
Microglia
Spider-like phagocytes
Dispose of debris
Ependymal cells
Line cavities of the brain and spinal cord
Circulate cerebrospinal fluid
Figure 7.3b, c
Slide 7.6
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23. Nervous Tissue: Support Cells
Oligodendrocytes
Produce myelin sheath around nerve fibers in the central nervous system
Figure 7.3d
Slide 7.7a
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

24. Nervous Tissue: Support Cells
Satellite cells
Protect neuron cell bodies
Schwann cells
Form myelin sheath in the peripheral nervous system
Figure 7.3e
Slide 7.7b
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25. Nervous Tissue: Neurons
Neurons = nerve cells
Cells specialized to transmit messages
Major regions of neurons
Cell body – nucleus and metabolic center of the cell
Processes – fibers that extend from the cell body
Slide 7.8
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26. Neuron Anatomy Cell body
Nissl substance – specialized rough endoplasmic reticulum
Neurofibrils – intermediate cytoskeleton that maintains cell shape
Figure 7.4a
Slide 7.9a
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27. Neuron Anatomy Cell body Nucleus Large nucleolus Figure 7.4a
Slide 7.9b
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

28. Neuron Anatomy Extensions outside the cell body
Dendrites – conduct impulses toward the cell body
Axons – conduct impulses away from the cell body
Figure 7.4a
Slide 7.10
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29. Axons and Nerve Impulses
Axons end in axonal terminals
Axonal terminals contain vesicles with neurotransmitters
Axonal terminals are separated from the next neuron by a gap
Synaptic cleft – gap between adjacent neurons
Synapse – junction between nerves
Slide 7.11
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30. Nerve Fiber Coverings
Schwann cells – produce myelin sheaths in jelly-roll like fashion
Nodes of Ranvier – gaps in myelin sheath along the axon
Figure 7.5
Slide 7.12
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31. Neuron Cell Body Location
Most are found in the central nervous system
Gray matter – cell bodies and unmylenated fibers
Nuclei – clusters of cell bodies within the white matter of the central nervous system
Ganglia – collections of cell bodies outside the central nervous system
Slide 7.13
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32. Assignment Create a diagram of a neuron. Identify its parts
Color the parts for distinction
Page 206

33. Closure
I will…..compare a nerve to an electrical cord and explain why there are similarities.

34. Human A&P Warm Up
Identify examples of support cells. What is the general term given to these cells?
Why is it important that we understand these cells in relation to disease?
Neuroglia
The support cells are necessary for healthy nervous tissue

35. Objective
We will…..explain the action potential that allows for messages to be sent in the human body.

36. Functional Classification of Neurons
Sensory (afferent) neurons
Carry impulses from the sensory receptors
Cutaneous sense organs
Proprioceptors – detect stretch or tension
Motor (efferent) neurons
Carry impulses from the central nervous system
Slide 7.14a
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37. Functional Classification of Neurons
Interneurons (association neurons)
Found in neural pathways in the central nervous system
Connect sensory and motor neurons
Slide 7.14b
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

38. Neuron Classification
Figure 7.6
Slide 7.15
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39. Functional Properties of Neurons
Irritability – ability to respond to stimuli
Conductivity – ability to transmit an impulse
The plasma membrane at rest is polarized
Fewer positive ions are inside the cell than outside the cell
Slide 7.17
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40. Starting a Nerve Impulse
Depolarization – a stimulus depolarizes the neuron’s membrane
A deploarized membrane allows sodium (Na+) to flow inside the membrane
The exchange of ions initiates an action potential in the neuron
Figure 7.9a–c
Slide 7.18
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41. The Action Potential
If the action potential (nerve impulse) starts, it is propagated over the entire axon
Potassium ions rush out of the neuron after sodium ions rush in, which repolarizes the membrane
The sodium-potassium pump restores the original configuration
This action requires ATP
Slide 7.19
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42. Nerve Impulse Propagation
The impulse continues to move toward the cell body
Impulses travel faster when fibers have a myelin sheath
Figure 7.9c–e
Slide 7.20
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43. Continuation of the Nerve Impulse between Neurons
Impulses are able to cross the synapse to another nerve when……
Neurotransmitter is released from a nerve’s axon terminal
The dendrite of the next neuron has receptors that are stimulated by the neurotransmitter
An action potential is started in the dendrite
Slide 7.21
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44. How Neurons Communicate at Synapses

45. Assignment Create foldable of brain and its 4 major parts:
Cerebral hemisphere
Diencephalon
Cerebellum
Brain stem

46. Closure
What is the transmission of the depolarization wave along the neuron’s membrane?
What is the state in which the resting potential is reversed as sodium ions rush into the neuron?
Action potential
Depolarization