2A.1 INTRO TO NEURO Flashcards
What are the 2 functions of the nervous system?
Enables the body to react to continuous change in its internal and external environments
Controls and integrates bodily activity
What are the 2 specialized cells in the nervous system?
Neurons=sensory + motor
Neuroglia=Schwann cells (and others)
- Non excitable cells supporting, insulating and nourishing neurons
Characteristics of neurons?
Transmit information
myelinated cells transmit signals faster
Types:
Multipolar motor neuron
Pseudounipolar sensory neurons
Characteristics of Neuroglia
-Nonneuronal, nonexcitable cells
-5x as abundant as neurons
-Support cells for neurons:
Supporting, insulating & nourishing
-CNS: oligodendroglia, astrocytes, ependymal cells & microglia
-PNS: satellite cells, Schwann cells
Myelination: CNS - Oligodendrocyte
- Forms several myelin sheaths
- Myelinates sections of several axons
Myelination: PNS- Schwann Cell
-Forms one myelin sheath
- Myelinates on section of an axon
Peripheral vs Central Neuropathy
CNS: Multiple Sclerosis
-slow progression
- onset between 20-50
- life expectancy decreases 7-14 years, no cure but remission can occur
> Oligodendrocytes wont repair themselves
> Secondary demyelination due to high ratio of axons myelinated by a single oligodendrocyte
Peripheral vs Central Neuropathy: PNS - Gullian-Barre Syndrome
-progression over days to weeks
- afflicts any age (more common <40)
- 80-90% recover within . 2-4 weeks
> schwann cells can dedifferentiate, proliferate and remyelinate bare axons over time
Anatomical/structural of CNS and PNS
Central Nervous System
- Brain
- Spinal Cord
Peripheral Nervous System
- Everything else
Nervous System Structure: Functional
Autonomic Nervous System
- Viscera (involuntary smooth muscle
- Glands
Somatic Nervous System
- Everything else
