Topic 19: Nervous System - Cell Types - Neurons Flashcards
1
Q
What are the two cell types?
A
-Neurons
- Neuroglia
2
Q
What is the function of neurons (2)
A
- make up CNS and PNS
- conduct impulses
3
Q
Why are neurons mostly irreplaceable? (2)
A
- mostly amitotic (do not undergo mitosis)
- exceptions are taste, olfactory, memory
4
Q
What are the structures of a neuron? (4)
A
- cell body
- RER
- Nuclei
- ganglia
5
Q
What is the cell body of a neuron?
A
typical organelles
6
Q
What is the RER of a neuron called?
A
Nissl bodies
note that when stained. it causes cell body to look gray
7
Q
What is the nuclei of a neuron?
A
- groups/clusters in CNS
8
Q
What is the ganglia of a neuron?
A
groups/clusters in PNS
9
Q
What are the two processes from the cell body of a neuron?
A
- dendrites
- axon
10
Q
What do dendrites receive?
A
- receive incoming messages and relay to cell body
11
Q
What do axons do?
A
- carry impulses away from cell body
- note that there’s only one axon, but can have multiple dendrites
12
Q
What is the axon hilock?
A
- where axon meets cell body
13
Q
What is the axon terminal?
A
- typically branched with synaptix end bulbs (enlarged tips)
14
Q
What is a myelinated axon? (3)
A
- wrapped in many layers of cell membrane from either:
- schwann cells (PNS)
- Oligodendrocytes (CNS)
15
Q
What does myelin provide?
A
electrical insulation
