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Bio Chapter8
Goodcare Bio Chap 8 LPN
Question | Answer |
---|---|
Working Unit of All Nervous Tissue | The Neuron |
The Nervous System has 2 Anatomic Divisions | The Central Nervous System (CNS) and The Peripheral Nervous System (PNS) |
The Central Nervous System (CNS) | the brain and spinal cord |
The Peripheral Nervous System (PNS) | all nerves outside the CNS including those branching directly off of the brain or spinal cord |
Neurons are actually composed of three major parts | the Cell Body (contains the nucleus) Dendrites and Axons |
A neuron can only carry an impulse in one direction, so nerves must be paired. True or False A | True |
Afferent neurons | Carry messages to the spinal cord from input sensors (they are also called sensory nerves.) |
Efferent neurons | Carry messages to muscles, glands, organs, etc to perform an action (they are called motor nerves.) |
Nerve protective “wrappings" | the endoneurium, perineurium, and the epineurium. |
Neuroglial Cells (4 types) | Astrocytes Oligodendrocytes Microglial cells Ependymal cells |
Astrocytes | provide physical support as well as nutrients and ions within nerve tissue. |
Oligodendrocytes | provide myelin sheaths around axons of neurons. |
Microglial cells | support neurons and phago-cytize bacteria and debris. |
Ependymal cells | form epithelia-like mem-brane to cover and line specialized brain and spinal cord parts |
Aspects of Nerve Impulses | The Resting State Changes in Membrane Potential Action Potential Rising Phase Falling Phase The Role of Myelin in Conduction |
4 Neurotransmitters | Norepinephrine Serotonin Dopamine Acetylcholine |