1. The Control Systems of the Body
Local Control
Autocrine -
Paracrine -
Long Distance Control
Endocrine System
Slower Response, Broad, Long Lasting
Nervous System
Faster Response, Specific, Brief

2. The Nervous System Overview Neurophysiology Central Nervous System
Peripheral Nervous System
Autonomic N.S.
Somatic N.S.

3. Overview of the Nervous System

4. PNS
CNS
Sensory Pathway
Receptors
Interneuron
(Integration)
Motor Pathway
Effector
Tissue

5. A Typical Neuron Dentrites Cell Body Axon Axon Terminal with End Bulb
incoming info.
integration of info.
Nodes of
Ranvier
outgoing info.
release of neurotransmitter

7. Graded Potentials Action Potentials
Localized change in membrane potential that varies in magnitude
and is decremental.
Action Potentials
Rapid reversal in membrane potential (due to changes in ion
permeability), with constant magnitude and is non-decremental.

9. Action Potentials "All or none" event
Signal does not diminish over distance
There are 4 Phases in an Action Potential:
1. Threshold
2. Depolarization
3. Repolarization
4. Hyperpolarization

12. Refractory Periods Absolute Refractory Period:
Relative Refractory Period:

13. Summation of Graded Potentials
Temporal Summation:
As the frequency of a single stimuli increases, the changes in membrane potential can be added and its magnitude can increase.
Spatial Summation:
As multiple simultaneous stimuli occur at different places on the neuron, the changes in membrane potential can be added and its magnitude increased or decreased.

16. Graded vs. Action Potentials
1. Magnitude varies
1. No variation - All or None
2. Decremental
(passive spread)
2. Non-decremental
(self-regenerating)
3. No Refractory Periods
in Graded Potentials
3. Two Refractory periods:
Absolute and Relative
4. Summation is possible
4. No Summation possible
5. Trigger: NT's, hormones
5. Trigger: Threshold
6. Occurs at cell body
(direction can vary)
6. Occurs at axon hillock (one way direction)

17. How fast can a signal travel down an axon?

18. Speed of Conduction of Signal
Small Diameter
Large Diameter

20. Speed of Conduction of Signal
Small Diameter
Large Diameter
Temperature
Axon Myelination

22. The Biochemistry of the Synapse

23. Stopping Signal Transmission
Stop the Impulse (Pre-Synaptic AP)
Clear Away the Synaptic Cleft
1. Diffusion away from Receptors.
2. Enzymatic Degradation of NT.
3. Re-uptake of NT by Pre-Synaptic cell.

26. Post-Synaptic Cell Responses
Ionotropic Effect
Metabotropic Effect

28. Neuronal Pathways
Divergent:

29. Neuronal Pathways
Convergent:

30. Pre- and Postsynaptic Inhibition and Facilitation
The Presynaptic terminal
Inhibitory neuron(s) – less NT released
Excitatory neuron(s) – more NT released
The Postsynaptic membrane and receptors
- Receptor numbers
- Degradation rates
- Permeability

33. The Different Glial Cells