1. Baroque Period: Annibale Carracci (~1590)

2. Introduction to the Nervous System Chapter 8

3. Structure & Function: Systems – CNS, PNS, ANS Central Control (Motor Control) Integration of Information Monitor and Regulate Homeostasis Think and Feel

4. Structure and Function: Cellular Components Neurons: Excitable cells – “wiring” “Signal Senders” Neuroglia: Support, Nurturing, Insulation

5. Neurons: Important Features: EXCITABLE Membrane: Able to regulate the movement of ions (charge) across and along membrane SIGNAL TRANSDUCTION DO NOT Replicate: Damaged cells cannot be replaced!

6. Neurons: Structure & Function Cell Body (Soma): Life Support Protein Synthesis Single Nucleus, RER (Nissel bodies) Axon: Longest process transmit messages away from cell body Dendrites: Multiple processes off cell body – receive messages

7. Neurons: Cell Body Dendrite Axon

8. Neuron Classification: Multipolar: “multi-” many processes Majority: Single axon, many dendrites Bipolar: “bi-” 2 processes: Found in some sensory organs Unipolar: “uni-” 1 process (with branches) Sensory Afferent neurons

9. Support Cells: Neuroglia “Nerve Glue”: Although subordinate, many neurological diseases rest in Glial Cell dysfunction! Multiple Sclerosis: Schwann Cells Alzheimer’s Disease: Astrocytes Astrocytoma: Aggressive brain cancer

10. Neuroglia: Distinguishing Features Able to Replicate Importance in Nervous System Function is VASTLY underestimated! Evidence is Mounting: 1. Nurturing Roll 2. Signaling Roll (Memory?)

11. Structural Support Cells: Astrocytes: Maintaining extra- cellular environment – blood brain barrier. ALSO: Clean up NT’s Ependymal Cells: Ciliated epithelial cells lining ventricles and canals: Maintain cerebral spinal fluid (CSF)

12. Myelinating Glia: Oligodendrocytes: Insulating axons in the CNS Schwann Cells: Insulating axons in the PNS MYELIN: High Fat insulation speeds up signal transmission by “leaps and bounds”

13. Excitable Cells: It’s All About Membranes! Membrane channels and Pumps keep Na + OUT: This makes the outside RELATIVELY Positive: Resting (waiting) Membrane Potential Resting Membrane Potential = -70 mV

14. Interactive Neurophysiology: Objectives What are the Relative concentrations of various ions inside and outside the neuron? How do membranes “select” which ions are in or out? What is the “equilibrium potential” for K + ?

15. More Objectives : How does the concentration of Na + and K + determine the resting membrane potential? Why is the Na + /K + pump needed to maintain the resting membrane potential?

16. Assignment: Write 3 questions: Remaining confusion about the excitable membranes of neurons so that you understand: How and why neurons maintain a Resting Membrane Potential of –70 mV?