1. Neurons & Neuroglia
Lecture 6

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

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

4. Dendrites & Soma
Receives & Integrates information
electrical signal within ~

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

6. By function (connections)
Sensory
Motor
Interneuron

7. By morphology (# of neurites)
Multipolar
Bipolar
Unipolar

8. Neurons vs. Nerves Neurons - cells microscopic
Nerves - bundles of axons
seen with naked eye ~

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

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

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

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

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

14. Microglia Immune-like function macrophage foreign cells
cellular debris ~