1. + Peripheral Nervous System

2. + PERIPHRAL NERVOUS SYSTEM PNS LIES OUTSIDE THE CENTRAL NERVOUS SYSTEM COMOSED OF NERVES NERVES = BUNDLES OF AXONS WE CALL THEM NERVE FIBERS SENSORY FIBERS CARRY INFORMATION TO THE CNS MOTOR FIBRS CARR INFORMATION AWAY FROM THE CNS

3. Fig. 17.15a bundle of nerve fibers nerve single nerve fiber

4. + Cranial Nerves Humans have 12 pairs of cranial nerves attached to the brain Some of these nerves bring information from the sense organs to the brain other cranial nerves control muscles other cranial nerves are connected to glands or internal organs such as the heart and lungs.

5. + Cranial Nerves

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7. + Spinal Nerves 31 pairs Emerge from openings between vertebral column and spinal cord Dorsal root (back) Contains sensory fibers that conduct impulses toward the spinal cord Dorsal Root gangilon Cell body Ventral root (front) Contains motor fibers that conduct impulses away from the spinal cord

8. spinal nerve dorsal root ventral root dorsal root ganglion

9. + PNS PNS divided into 2 parts Somatic system Autonomic system

10. + Somatic Nervous System responsible for carrying motor and sensory information both to and from the CNS Responsible for all voluntary muscle movements and processing sensory information (hearing, touch, sight) Made up of nerves that connect to skin, sensory organs and skeletal muscles

11. + Autonomic Nervous System regulates the functions of our internal organs like the heart, stomach and intestines. We are often unaware of the ANS because it functions involuntary and reflexively For example, we do not notice when blood vessels change size or when our heart beats faster. 2 divisions Sympathetic Parasympathetic

12. + ANS The ANS is most important in two situations: In emergencies that cause stress and require us to "fight" or take "flight" (run away) In non-emergencies that allow us to "rest" and "digest."

13. + Sympathetic Division It is a nice, sunny day...you are taking a nice walk in the park. Suddenly, an angry bear appears in your path. Do you stay and fight OR do you turn and run away? These are "Fight or Flight" responses. In these types of situations, your sympathetic nervous system is called into action - it uses energy - your blood pressure increases, your heart beats faster, and digestion slows down.

14. + Parasympathetic Division It is a nice, sunny day...you are taking a nice walk in the park. This time, however, you decide to relax in comfortable chair that you have brought along. This calls for "Rest and Digest" responses. Now is the time for the parasympathetic nervous to work to save energy This is when blood pressure can decrease, pulse rate can slow, and digestion can start.

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16. + ANS

17. + PNS https://www.youtube.com/watch?v=QY9NTVh-Awo