Neurons Flashcards
1
Q
What is a neuron?
A
Nerve cells that process and transmit messages through electrical and chemical signals
2
Q
What is a sensory neuron?
A
- Carry messages from the PNS to the CNS
- Have long dendrites and short axons
3
Q
What is a relay neuron?
A
- Connect the sensory neurons to the motor or other relay neurons
- Have short dendrites and short axons
4
Q
What is a motor neuron?
A
- Connect the CNS to effectors such as muscles and glands
- Have short dendrites and long axons
5
Q
What is the structure of a neuron?
A
- Nucleus
- Dendrites
- Cell body
- Axon
- Myelin sheath
- Nodes of Ranvier
- Terminal buttons
6
Q
What is the cell body?
A
- Factory of the neuron
- Contains the nucleus and produces all of the necessary proteins that a neuron requires to function
7
Q
What is the nucleus?
A
Contains the genetic material within the neuron
8
Q
What are dendrites?
A
- Branch-like features that protrude from the cell body
- Carry nerve impulses from neighbouring neurons towards the cell body
9
Q
What is the axon?
A
Carries the electrical impulse from the cell body, down the length of the neuron
10
Q
What is the myelin sheath?
A
- Fatty layer, which surrounds and protects the axon
- Helps to speed up the electrical transmission of the impulse
11
Q
What are the nodes of Ranvier?
A
- Gaps between the myelin sheath
- Speed up the transmission of the impulse, by forcing it to ‘jump’ across the gaps along the axon
12
Q
What are the terminal buttons?
A
- Located at the end of the axon
- Communicate with the next neuron that is on the other side of the synaptic cleft