The flashcards below were created by user
mc166589
on FreezingBlue Flashcards.
-
What are the basic structures of the neuron?
- Cell body
- Axon
- Dendrite
- Myelin sheaths
-
Where can cell bodies of neurons be found?
-
What function does the cell body fufill in the neuron?
Controls metabolism
-
Besides the normal organelles, what two organelles do cell bodies have?
-
What are neurofibrils?
- microtubules - move material
- (neurotransmitter, from cell body to end of axon)
-
Describe the structure of dendrites.
- Highly branched
- Very numerous
- Relatively short
-
What is the function of dendrites?
receive and transmit impulses toward cell body
-
How many axons are connected to a cell body?
One
-
Where do axons connect to on a cell body?
Axon hillock
-
Describe the structure of an axon.
- Very in length
- May have branches
- At end, many short terminal branches may occur, each ending in synaptic knobs or bulbs that containsecretory vesicles filled with neurotransmitter.
-
What is the function of an axon?
transmit nerve impulses away from cell body to another nerve cell, or to an effector cell.
-
When do cell bodies and dendrites contain myelin sheaths?
Never
-
What are the two types of axons and where can they be found?
- Myelinated - white matter
- Unmyelinated - gray matter
-
What forms myelin sheaths in the PNS?
Schwann cells
-
The outter layer of the myelin sheaths in the PNS is called what?
Neurolemma
-
What gives the white appearence of myelin in the PNS?
The high lipid content.
-
What are the nodes of Ranvier and what are their functions?
- Area between schwann cells that lack myelin.
- These act as conductive segments that allow nerve impulses to travel.
-
Oligodendrocytes extend long processes that form _____ in the CNS.
myelin
-
cell bodies and cytoplasm remain in spaces between neurons in the CNS, which means that there are no _____.
Neruolemma
-
Nodes of Ranveir occur in what?
-
Because of the absence of _____ in the CNS, it is unlikely that neurons will regenerate after injury.
Neurolemma
-
Myelination development is completed when?
adolescence
|
|