Organisms Respond to Changes in their Internal and External Environments: Nervous Coordination - Nerve Impulses, Structure of a Motor Neurone Flashcards
1
Q
What is a motor neurone?
A
- Neurones that carry information from the CNS to the effectors
2
Q
List the different structural features of a myelinated motor neurone
A
- Dendrites
- Axon
- Myelin sheath
- Node of Ranvier
- Cell body
3
Q
Draw and label the structure of a myelinated motor neurone
A
4
Q
What are dendrites?
A
- Transmits impulses toward the cell body
- Connects with other neurones
5
Q
What is an axon?
A
- Transmits impulses away from the cell body
6
Q
What is a myelin sheath?
A
- Layer that allows electrical impulses to transmit quickly and efficiently along the nerve cells
- Made of Schwann cells
7
Q
What are nodes of Ranvier?
A
- Gaps between adjacent Schwann cells
8
Q
What does the cell body contain?
A
- Organelles
- Nucleus
- Many RERs
9
Q
Why does the cell body contain nuclei and many RERs?
A
- To make neurotransmitters, which are proteins
10
Q
Describe adaptations of the axon
A
- Schwann cells wrap around the axon until up to a hundred layers of lipid and protein membranes are present
- Provides protection from surrounding tissue fluid
- Provides electrical insulation
