Updated 2009-06-20 14:41


Question Answer
The function of the ascending neuron pathway is ____.Input.
The function of the descending neuron pathway is ____.Output.
Describe the function of astrocytes.Cling to neurons and their synaptic endings, and cover nearby capillaries, supporting and bracing the neurons and anchoring them to their nutrient supply lines, the blood capillaries.
Have a role in making exchanges between capillaries and neurons, in guiding the migration of young neurons, in synapse formation, and in helping to determine capillary permeability.
"Mopping up” leaked potassium ions and recapturing (and recycling) released neurotransmitters.
Where will you find ependymal cells?They line the central cavities of the brain and the spinal cord, where they form a fairly permeable barrier between the CSF that fills those cavities and the tissue fluid bathing the cells of the CNS
Review the structure of a nerve cell.
What are some characteristics of nerve cells.Have extreme longevity.
Generally amitotic (cannot divide).
High metabolic rate.
What is the purpose of Nissl bodies?The neuron cell body’s protein- and membrane-making machinery, consisting of clustered free ribosomes and rough endoplasmic reticulum (ER).
At what sites does the neuron receive input?Dendrites convey incoming messages toward the cell body
What does it mean to say that the axon terminal is secretory?
From what do the secretory vessels of the axon terminal derive?
Where does myelin come from?
How does myelin aid in rapid conduction?
What are white matter and gray matter in the CNS?
Describe the structure and function of unipolar neurons.
Where do you find unipolar neurons?
What is a ganglion?
Review neuron types: afferent, efferent, interneuron.
A potential difference across a membrane is measures in ____.
Flow of charge across a membrane occurs through specific ____ ____.
By which mechanisms can gated channels can be opened?
Describe the gradients of sodium and potassium ions at resting potential.
Describe the events of membrane depolarization and repolarization.
What contributes to hyperpolarization?
What are graded potentials?
What are action potentials?
What would constitute a threshold stimulus?
What does it mean that an action potential is "all or none"?
How do strong stimuli differ from weak with regard to the action potential?
What chemical event constitutes the absolute refractory period?
What chemical event constitutes the relative refractory period?
How do neurotransmitters affect membrane depolarization at the synapse?
How do excitatory synapses behave versus inhibitory ones?
What is a second messenger system and which neurotransmitters utilize it for producing effects postsynaptically?
Question Answer
What are they glial cells of the CNS?Astrocytes, microglia, ependymal cells, oligodendrocytes.