1. Neurons and Nervous Systems

2. Neurons and Nervous Systems
Neuron structure
Generating and Conducting Nerve Impulses
Synapses

3. Identify: Dendrites Form = Function Nucleus Cell body (soma) Axon
Figure Neurons (Part 1)
Identify:
Dendrites
Nucleus
Cell body (soma)
Axon
Synapse
Myelin?
Axon terminal
Form = Function

4. Nervous Systems: Cells and Functions
Myelin is the covering produced by Schwann cells and oligodendrocytes.

5. Figure 44.3 Wrapping Up an Axon

6. Neurons: Generating and Conducting Nerve Impulses
The difference in voltage across the plasma membrane of a neuron is called its membrane potential.
In an unstimulated neuron, the voltage difference is called a resting potential.
The membrane potential of a resting axon is about –60 millivolts (mV). The inside of the cell is more negative than the outside.

8. Figure 44.5 Ion Pumps and Channels

9. Figure 44.4 Measuring the Resting Potential (Part 2)

10. Neurons: Generating and Conducting Nerve Impulses
An action potential is the sudden and rapid reversal in voltage across a portion of the plasma membrane. For 1 to 2 milliseconds, the inside of the cell becomes more positive than the outside.
Nerve impulses are action potentials that travel along axons.

11. Figure 44.9 The Course of an Action Potential

12. Figure 44.10 Action Potentials Travel along Axons (Part 1)

13. Figure 44.10 Action Potentials Travel along Axons (Part 2)

14. Figure 44.10 Action Potentials Travel along Axons (Part 3)

15. Figure 44.13 The LAST STEP: the Synapse

16. ALL VIDEO CLIPS provided by “BITTERSWEET BIOLOGY”
Synapse Video clip
Synapse video clip
ALL VIDEO CLIPS provided by
“BITTERSWEET BIOLOGY”