1. ORGANIZATION OF THE NERVOUS SYSTEM

2. FUNCTIONS SENSORY SENSORY MOTOR MOTOR COGNITIVE COGNITIVE

3. ANATOMICAL ORGANIZATION of the NERVOUS SYSTEM

4. Central Nervous System (CNS) Unpaired, bilaterally symmetrical structures extending along the longitudinal axis of the midsagittal plane of the body. Unpaired, bilaterally symmetrical structures extending along the longitudinal axis of the midsagittal plane of the body. Structures arising directly from the neural tube. Structures arising directly from the neural tube. Includes: Includes:Brain Spinal cord

5. Peripheral Nervous System (PNS) (PNS) Made up of transmission pathways carrying information between the CNS and external/internal environments. Made up of transmission pathways carrying information between the CNS and external/internal environments. Afferent (sensory) pathways: Afferent (sensory) pathways: Carry information to the CNS. Efferent (motor) pathways: Efferent (motor) pathways: Carry information from the CNS.

6. Peripheral Nervous System Includes: Includes: Cranial nerves (12 pairs) Spinal nerves (31 pairs) Also includes sensory receptors in skin and wall of gut tube as well as in tendons and skeletal muscles. Also includes sensory receptors in skin and wall of gut tube as well as in tendons and skeletal muscles. Also includes motor end plates between motor neurons and skeletal muscle fibers. Also includes motor end plates between motor neurons and skeletal muscle fibers.

7. Autonomic Nervous System May be considered a subdivision of the PNS. May be considered a subdivision of the PNS. Entirely motor. Entirely motor. Innervates smooth muscle and glands (viscera) Innervates smooth muscle and glands (viscera)

8. ANS Subdivisions Sympathetic system Sympathetic system (fight or flight) Also called thoracolumbar Parasympathetic system Parasympathetic system (feed and breed) Also called craniosacral

10. Parts of a Neuron Cell body: Cell body: Trophic unit Perikaryon Dendrites: Dendrites: Receptive unit Axon: Axon: Conductive unit

12. Cell Body That part of a neuron that encloses the nucleus and other organelles necessary to maintain and repair neuron. That part of a neuron that encloses the nucleus and other organelles necessary to maintain and repair neuron.

13. Cell Body Organelles Nucleus Nucleus Golgi apparatus Golgi apparatus RER RERRibosomes =Nissl substance

15. Dendrites Branches off the cell body that carry information to the cell body. Branches off the cell body that carry information to the cell body. Usually several to many. Usually several to many. Relatively short. Relatively short. Often branched. Often branched. Have receptors for neurotransmitters. Have receptors for neurotransmitters. Conduct local potentials. Conduct local potentials.

16. Axon That part of the neuron that carries information to another neuron or muscle cell. That part of the neuron that carries information to another neuron or muscle cell. Usually relatively long. Usually relatively long. Single. Single. Conducts action potential (nerve impulse) Conducts action potential (nerve impulse)

17. Axon Ends in short branched processes called: Ends in short branched processes called:Telodendria: Give off endings called terminal boutons. Terminal boutons contain synaptic vesicles of neurotransmitters. May have collateral branches. May have collateral branches.

19. Axon Cell membrane is called the axolemma. Cell membrane is called the axolemma. Cytoplasm is called the axoplasm. Cytoplasm is called the axoplasm.

20. Axon Contains: Contains:MitochondriaNeurofilamentsNeurotubules

21. Axonal Transport Anterograde Anterograde Retrograde Retrograde Slow transport Slow transport Fast transport Fast transport

22. Axon Covered by neurolemma: Covered by neurolemma: Made up of Schwann cells. Often myelinated: Often myelinated: Myelin is formed by Schwann cells. Note: axon is only part of neuron that is ever myelinated. Note: axon is only part of neuron that is ever myelinated.

23. General Terminology Nucleus: Nucleus: Aggregation of dendrites and nerve cell bodies in the CNS. Ganglion: Ganglion: Aggregation of dendrites and nerve cell bodies in the PNS.

24. General Terminology Nerve: Nerve: Bundle of fibers (axons) in the PNS. Tract: Tract: Bundle of fibers (axons) in the CNS. Commissure: Commissure: Tract in the CNS that crosses from one side to the other.

25. General Terminology White matter: White matter: Areas of myelinated axons. Gray matter: Gray matter: Areas of unmyelinated axons, cell bodies, and dendrites.

26. Functions of the CNS Refer to p. 63 in syllabus Refer to p. 63 in syllabus

27. Spinal Nerve Branches Dorsal primary ramus Dorsal primary ramus Ventral primary ramus Ventral primary ramus Ramus recurrens Ramus recurrens White ramus communicans White ramus communicans Gray ramus communicans Gray ramus communicans

28. Spinal Nerve Branches Paravertebral ganglion Paravertebral ganglion Splanchnic nerve Splanchnic nerve Prevertebral ganglion Prevertebral ganglion

29. Reflex Arc Afferent (sensory) pathways: Afferent (sensory) pathways:Somatic. Visceral (splanchnic). Efferent (motor) pathways: Efferent (motor) pathways:Somatic. Visceral (splanchnic). Association neurons (interneurons). Association neurons (interneurons).

30. Synapse Components: Components: Presynaptic membrane: With synaptic vesicles filled with neurotransmitters. Synaptic cleft: Postsynaptic membrane: With receptors for neurotransmitters. Monosynaptic pathways. Monosynaptic pathways. Polysynaptic pathways. Polysynaptic pathways.