The Nervous System

1. The Nervous System How Does It Work?

2. Your nervous system has three components… • Brain • Nerves • Spinal cord

3. Subdivisions of the nervous system • the brain • the spinal cord • the peripheral nerves • the autonomic nervous system • somatic nervous system • the enteric nervous system

4. Frontal lobe • Temporal lobe • Parietal lobe • Occipital lobe • Structure relates to function?

5. Axon Myelin sheath Node of Ranvier Presynaptic terminals An archetypal neuron • Cell body (soma) • Dendrite • Axon hillock (= initial segment)

6. What you should know • Surface structure of the brain including meninges, cerebellar cortex, cerebral cortex and its division into four lobes, cranial nerves • Gross internal structure of the brain including ventricles, white matter, grey matter, corpus callosum, thalamus, midbrain, pons, medulla, basal ganglia and internal capsule • Gross structure of the spinal cord including dorsal horn, ventral horn, dorsal root, ventral root, dorsal column, lateral column, ventral column. • Structure of a neurone including soma, dendrites axon hillock, axon, myelin, node of Ranvier, presynaptic terminal. Types of glia

7. The Most Important Part of the Nervous System… • Your brain controls everything that happens in your body.

8. The brain has two sides. • The left side of the brain controls the right side of the body. • The right side of the brain controls the left side of the body.

9. Nerves are like telephone lines. • They send messages all over your body. • These messages move through your body faster than you can blink your eyes.

10. Nerves travel through the spinal cord. • Your spinal cord is like an extension cord that runs down the center of your back. • It is protected by the backbone.

11. Interesting Facts • Each side of the brain controls the opposite side of the body. • Your brain is full grown by age 6. • It weighs about three pounds. • Your brain is made mostly of water. (85%)

12. What if you had no brain or nerves? • You wouldn’t be able to see, hear, smell, or talk.

13. Healthy Habits • Exercise • Do challenging activities that make you think • read, read, read • Lift things carefully – use your legs, not your back

14. Components Brain – control center Nerves – carry messages Spinal cord – a thick bundle of nerves Summary Functions • sends messages to the rest of the body • controls all of the body functions