1. The Nervous System
A&P Spring 2017

2. I. Organization of the Nervous System
Structural Classification
Central Nervous System (CNS)
The Brain
The Spinal Cord
Peripheral Nervous System (PNS)
Nerves that extend from the CNS
i. Serve as communication lines that link all parts of the body to the CNS

4. B. Functional Classification (PNS only) 1. Sensory Division a
B. Functional Classification (PNS only) 1. Sensory Division a. nerves that send impulses TO the CNS from sensory receptors 2. Motor Division a. Nerves that carry impulses FROM the CNS to organs, muscles and glands

6. 3. Somatic NS (Subdivision of Motor)
a. voluntary control of skeletal muscles
4. Autonomic NS (Subdivision of Motor)
a. regulates involuntary events
b. also has 2 subdivisions
i. Sympathetic- Fight or Flight
ii. Parasympathetic- Rest and Digest

8. Central Nervous System Peripheral Nervous System
The Nervous System
Central Nervous System
Peripheral Nervous System
Sensory
Motor
Somatic
Autonomic
Sympathetic
Parasympathetic

9. Bell Ringer
Create a diagram that shows the relationship between the following:
Central NS
Motor
Autonomic
Somatic
Peripheral NS
Sensory

10. II. Nervous Tissue: Structure and Function
Supporting Cells
Neuroglia (Glial Cells)
Found in the CNS
Astocytes
Microglia
Ependymal
Oligodendrocytes

12. b. Found in the PNS
Schwann cells
Satellite cells

13. Neuroglia Flipbook! Materials: 3 Sheets of paper Page of pictures
Stapler (will be passed around)
Glue stick
Scissors
Pen/Pencil

14. Cover Page
NEUROGLIA By: Your Name

15. Page 1
Found in the Central Nervous System

16. Page 2
Astrocytes star-shaped cells that anchor neurons to blood capillaries. Helps with exchange of oxygen and nutrients (Paste picture to the back of page 1)

17. Page 3
Microglia spiderlike cells that monitor the health of neurons. Dispose of debris such as dead brain cells and bacteria. (paste picture to the pack of page 2)

18. Page 4
Ependymal Cells Line the central cavities of the brain & spinal cord. Forms a protective cushion around the CNS. Cilia help circulate cerebrospinal fluid. (paste the picture to the back of page 3)

19. Page 5
Oligodendrocytes wrap around nerve fibers of the CNS to form an insulating cover called a “myelin sheath”. (paste the picture to the back of page 4)

20. Page 6
Found in the Peripheral Nervous System

21. Page 7
Satellite Cells Form a protective cushion around the PNS. (paste picture to the back of page 6)

22. Page 8
Schwann Cells Wrap around the nerve fibers of the PNS to form an insulating cover called a “myelin sheath” (Paste picture to the back of page 7)

23. Page 9
Summary CNS: PNS: Astrocytes Satellite Cells Microglia Schwann Cells Oligodendrocytes Ependymal Cells

24. Bell Ringer
What is the main purpose of ALL neuroglia?

25. B. Neurons 1. Anatomy a. Cell Body i. center of the neuron ii
B. Neurons 1. Anatomy a. Cell Body i. center of the neuron ii. Contains the nucleus and the usual cell organelles

26. b. Dendrites i. detect incoming messages (electrical signals) ii
b. Dendrites i. detect incoming messages (electrical signals) ii. “Listeners” c. Axon i. send messages out ii. “Talkers”

27. d. Axon Terminals i. End of the axon ii
d. Axon Terminals i. End of the axon ii. Contains chemicals that carry messages from one neuron to the next iii. Synaptic cleft is a gap between neurons

28. e. Myelin Sheath
i. material that insulates nerve axons
ii. Increases the rate of nerve impulses
f. Nodes of Ranvier
i. Space between myelin sheaths where the axon is exposed
ii. Impulses “Jump” to these spaces

30. 2. Classification a. Functional Groups i. Sensory (afferent) neurons ii. Motor (efferent) neurons iii. Interneurons (association)

31. b. Structural Groups i. Multipolar neurons ii. Bipolar neurons iii
b. Structural Groups i. Multipolar neurons ii. Bipolar neurons iii. Unipolar neurons

32. III. The Central Nervous System
Anatomy of the Cerebrum
Cerebral Hemispheres
Gyrus (gyri; plural)- ridges
Sulcus (sulci; plural)- shallow grooves
Fissures- deep grooves
Transverse Fissure- separates cerebrum from cerebellum
Longitudinal Fissure- separates cerebral hemispheres

34. 2. Lobes a. Frontal i. Primary motor area b. Parietal i
2. Lobes a. Frontal i. Primary motor area b. Parietal i. Primary sensory area c. Temporal i. Auditory area d. Occipital i. Visual area

36. 3. Cerebral White Matter a. inner most part of the brain b
3. Cerebral White Matter a. inner most part of the brain b. contains the “Corpus Callosum” i. a large nerve fiber ii. Connects the cerebral hemispheres

37. 4. Diencephalon a. located on the bottom i
4. Diencephalon a. located on the bottom i. sits on top of the brain stem b. 2 major structures i. Thalamus- relay station for sensory impulses ii. Hypothalamus- regulates body temperature, water balance and metabolism

39. B. Anatomy of the Brain Stem 1. Midbrain a
B. Anatomy of the Brain Stem 1. Midbrain a. Contains two large nerve fibers b. fibers serve as reflex centers i. vision reflex center ii. Hearing reflex center

40. 2. Pons
a. means “bridge”
b. involved with control of breathing

42. 3. Medulla Oblongata
a. merges with the spinal cord
b. contains several control centers
i. heart rate
ii. Blood pressure
iii. Breathing
iv. Swallowing
v. vomiting

44. C. Anatomy of the Cerebellum 1. “Little Brain” a
C. Anatomy of the Cerebellum 1. “Little Brain” a. divided into two hemispheres b. contains gray cortex on the outside c. white cortex in the center d. located on the bottom of occipital lobe

45. 2. Involved with balance & movement
a. ensures that skeletal muscle movements are smooth and precise
b. controls balance and equilibrium

46. D. Protection of the Central Nervous System 1
D. Protection of the Central Nervous System 1. Meninges- cover the brain and spinal cord a. Dura Mater i. Outermost layer ii. Very tough

48. b. Arachnoid Mater
i. middle layer
ii. Web-like
c. Pia Mater
i. Inner layer
ii. Thinnest
iii. Clings to the brain and spinal cord

50. 2. Cerebrospinal Fluid (CSF) a. Watery “broth” i
2. Cerebrospinal Fluid (CSF) a. Watery “broth” i. made from blood plasma b. surrounds brain and spinal cord i. acts as a protective cushion from some forms of trauma c. Continually moving i. forms and drains at a constant rate ii. Specific pressure is maintained

52. d. Lumbar (Spinal) Tap
i. used when testing for diseases that affect the CSF
ii. Patients have CSF withdrawn from their lower spine
iii. The change in pressure requires patients to remain laying down for hours after the procedure
iv. Failure to do so can result in an extremely painful “spinal headache”

54. E. Anatomy of the Spinal Cord 1. Enclosed in the vertebral column a
E. Anatomy of the Spinal Cord 1. Enclosed in the vertebral column a. actually ends just below the ribs i. 1st or 2nd Lumbar Vertebra

55. b. has 31 pairs of spinal nerves
i. nerves branch out from the vertebrae to serve nearby body areas
c. spinal nerves that serve the lower body bunch together
i. they must extend through the bottom of the vertebral column
ii. This grouping is called the “Cauda Equina” which means horse tail

58. 2. Spinal Nerve Roots a. Every spinal nerve connects to the spinal cord in two places i. connections are called “roots” ii. Connect to the front and back side b. Dorsal Roots i. “Back” roots ii. Beginning of Sensory Neurons c. Ventral Roots i. “Front” roots ii. Beginning of Motor Neurons

60. IV. Peripheral Nervous System
Cranial Nerves
We will make flash cards for each of the nerves and their functions.
There are 12 nerves, so you will need 12 flash cards!

61. I. Olfactory
Sense of smell

62. II. Optic
Sense of vision

63. III. Oculomotor
Movement of eyelids

64. IV. Trochlear
Movement of eyes up and down

65. V. Trigeminal
Sense of touch on the face; movement of jaw for chewing

66. VI. Abducens
Movement of eyes side to side

67. VII. Facial
Movement of facial muscles (facial expression)

68. VIII. Vestibulocochlear
Sense of balance and hearing

69. IX. Glossopharyngeal
Movement of pharynx for swallowing; sense of taste

70. X. Vagus
Movement of digestive organs

71. XI. Accessory
Movement of neck and shoulders

72. XII. Hypoglossal
Movement of the tongue

73. B. Structure of a Nerve 1. Parts of a nerve a
B. Structure of a Nerve 1. Parts of a nerve a. Nerve- bundle of fascicles b. Fascicle- bundle of nerve fibers (processes) c. Nerve fiber (Process)- axon of individual neuron cells

74. 2. Protective Coverings a. Endoneurium- covers the nerve b
2. Protective Coverings a. Endoneurium- covers the nerve b. Perineurium- covers the fascicles c. Epineurium- covers the nerve fibers (processes)

76. 3. Types of nerves a. Sensory i. sends impulses TOWARD the CNS b
3. Types of nerves a. Sensory i. sends impulses TOWARD the CNS b. Motor i. sends impulses AWAY from the CNS c. Mixed i. sends impulses in both directions ii. made of BOTH sensory and motor neurons