The document describes the structure and function of the nervous system. It discusses the central nervous system (CNS), which includes the brain and spinal cord, and the peripheral nervous system (PNS), which includes nerves and ganglia outside the CNS. The nervous system has sensory and motor divisions, with sensory receiving information and motor transmitting it. Neurons conduct nerve impulses while glial cells support neurons. The brain regions include the cerebrum, diencephalon, brain stem, and cerebellum. The spinal cord extends from the brain stem and is divided into sections.

1. Nervous System

2. Central vs. Peripheral Nervous System 1. Central Nervous System (CNS) : brain and spinal cord

3. Central vs. Peripheral Nervous System 2. Peripheral Nervous System (PNS) : cranial nerves, spinal nerves and ganglia * ( Ganglion =group of neuron cell bodies located outside CNS)

4. Sensory division vs. Motor division 1. Sensory Division : receives information FROM body and transmits it TO the CNS for processing a) Somatic Sensory component – receives sensory information from skin, joints, muscle, special senses b) Visceral Sensory component – receives sensory info from blood vessels and viscera 2. Motor Division : transmits info FROM the CNS TO muscles and glands a. Somatic motor component: innervates skeletal muscle b. Autonomic motor (Autonomic Nervous System) : innervates smooth muscle, cardiac muscle, and glands of viscera (organs)

5. NERVOUS TISSUE CELLS A. Neurons : respond to stimuli and conduct nerve impulses

6. NERVOUS TISSUE CELLS B. Glial Cells: support and protect neurons (maintenance)

7. NEURON COMPOSITION (p 104) A. Cell Body : B. Nucleus : C. Dendrites : D. Axon : E. Synapse:

8. NEURON CLASSIFICATION 1. Sensory (Afferent) Neuron : brings information TO the CNS 2. Motor (Efferent) Neuron : takes information FROM CNS to other parts of the body, cell body located in CNS 3. Interneuron (Association Neurons) : helps coordinate and integrate info between sensory and motor neurons, cell body located in CNS

9. GLIAL CELLS - PNS A. Satellite Cells : surround neuron cell bodies in spinal ganglia * ( Ganglion =group of neuron cell bodies located outside CNS) B. Schwann cells : myelinate axons in PNS

10. Glial Cells - CNS C. Astrocytes : regulate transfer of materials from blood to the brain - help the workings of "blood -brain barrier" D. Oligodendrocytes : myelinate axons in CNS E. Microglia : phagocytize damaged neurons F. Ependymal Cells : line central canal and ventricles - help circulate cerebrospinal fluid (CSF)

11. MYELINATION OF AXONS wrapping an axon with myelin

12. The Brain 4 Regions Cerebrum R & L Hemispheres Diencephalon Brain Stem Cerebellum

13. Brain – Cerebrum Largest Region Gyri (twisters) & Sulcus (grooves) Fissures (deep grooves) Longitudinal (hemispheres) Divide Lobes

14. Brain – Cerebrum (lobes) Parietal Lobe Somatic sensory area “ homunculus”

15. Brain – Cerebrum (lobes) Occipital Lobe Visual area

16. Brain – Cerebrum (lobes) Temporal Lobe Olfactory Deep inside

17. Brain – Cerebrum (lobes) Frontal Lobe Primary Motor Area Speech Language

18. Cerebrum Cerebral Gray Matter (Cortex) superficial Cerebral White Matter deeper Corpus Callosum connects hemispheres

19. Diencephalon (interbrain) Sits atop brain stem Enclosed by cerebrum Structures Thalamus Hypothalamus Epithalamus

20. Diencephalon Thalamus Relay station from spinal cord Crude impulse Pleasant vs. Unpleasant

21. Diencephalon Hypothalmus (“under the thalmus”) ANS (Emotional Visceral Brain) Body Temp, H 2 O balance, Metabolism Appetites (thirst, hunger) Pleasure & Pain

22. Diencephalon Epithalamus Pineal body (endocrine system) Choroid plexus (cerebrospinal fluid)

23. Brain Stem About size of thumb Areas Midbrain Convey impulses Pons Controls breathing Medulla Oblongata Heart rate, BP, Swallowing, Vomiting, etc.

24. Cerebellum Convoluted surface Precise timing of Skeletal muscles Balance “ Auto-Pilot”

25. Protection of Brain Meninges dura mater (tough mother) arachnoid mater pia mater (gentle mother) Cerebrospinal Fluid Eliminate waste Blood-Brain Barrier Least-permeable membrane in body

26. Spinal Cord Aprox. 17 in long Continuation of Brain Stem Ends Below ribs

27. Spinal Cord Gray Matter Posterior Horns (dorsal) Anterior Horns (ventral) CSF Central Canal Protection Vertebrae Dura mater Arachnoid Pia mater

28. Spinal Cord Cervical Thoracic Lumbar Sacral Coccygeal

29. Spinal Cord - Cervical 8 Cervical Nerves C1-C8 Diaphragm, Shoulders, Neck Damage may result in: Respiratory Paralysis

30. Spinal Cord - Thoracic T1-T12 Intercostal

31. Spinal Cord - Lumbar L1-L5 Lower abdomen, buttocks, anterior & medial thigh, hip muscles, skin of thigh Damage: Inability to flex hip Loss of cutaneous sensation Inability to adduct thigh

32. Spinal Cord – Sacral & Coccygeal S1-S5 + Coccygeal Nerve Lateral & posterior leg/foot, gluteus, lower trunk Damage: Inability to extend hip Inability to flex knee