1. Neurons & Neuroglia Lesson 3

2. Basic Cell Biology n Eukaryotic cells n Cell membrane n Nucleus l chromosomes n Cytoplasmic organelles l Mitochondria l Endoplasmic reticulum l ribosomes l microtubules & microfilaments ~

3. Neurons n Basic functional unit of N.S. l Specialized cell l All cells have same basic properties n Regulation of behavior n Information processing l Transmits l Integrates l Stores ~

4. Axon Terminal Dendrites + Soma Axon Hillock Myelin Sheath Neuron Anatomy

5. n Dendrites & Soma l Receives & Integrates information l electrical signal within ~

6. n Axon carries information away from soma l Electrical signal within l Axon terminal releases chemical message ~ Stimuli

7. By function (connections) Interneuron SensoryMotor

8. Unipolar BipolarMultipolar By morphology (# of neurites)

9. Neurons vs. Nerves n Neurons - cells l microscopic n Nerves - bundles of axons l seen with naked eye ~

10. Neuroglia n Neural support cells l local influence at synapse l no role long distance signaling n Functions l exchange molecules with neurons l physical support l maintains microenvironment l Blood-brain barrier l immune system ~

11. Astrocytes n Provide physical support n Regulating chemical content of extracellular fluid l localizes neurotransmitters l K+ concentration n Blood-brain Barrier (BBB) ~

12. BBB: Function n Maintains stable brain environment l large fluctuations in periphery n Barrier to poisons n Retains neurotransmitters & other chemicals n Regulates nutrient supplies l glucose levels l active transport ~

13. Typical Capillary Blood-Brain Barrier Fenestra Intercellular cleft Brain Capillary tight junction No fenestra astrocytes

14. Neuroglia: Myelin n Wrap around axon n Saltatory Conduction l faster transmission n CNS: oligodendrocytes n PNS: Schwann cells ~

15. Microglia n Immune-like function l macrophage l foreign cells l cellular debris ~