Neurons Flashcards
1
Q
What is a neuron? (5 points)
A
- A nerve cell.
- They make up the nervous system.
- They receive information and transmit it to other cells.
- Neurons are an essential part of a massive communication system within the body.
- Neurons are specialised to conduct electrical impulses.
2
Q
What are the 7 parts of a neuron?
A
- Cell body.
- Nucleus.
- Dendrites.
- Axon.
- Myelin sheath.
- Nodes of Ranvier.
- Axon terminals.
3
Q
What does the cell body do?
A
- Holds the nucleus.
4
Q
What does the nucleus do?
A
- Contains the genetic material for each neuron (the DNA).
5
Q
What do dendrites do?
A
- These carry electrical signals from other neurons.
6
Q
What do the axon do?
A
- This carries the electrical signal away from the cell body and down the length of the neuron.
7
Q
What does the myelin sheath do?
A
- A fatty layer that covers the axon. It is a ‘specialised’ feature of the neuron that speeds up the electrical signal (action potential).
8
Q
What are the nodes of Ranvier?
A
- These are gaps in the myelin sheath that make the signal go even faster- the signal ‘jumps’ across each gap.
9
Q
What are axon terminals?
A
- These are found at the end of the axon and are where synaptic transmission takes place.
10
Q
What are the 3 types of neurons?
A
- Sensory neurons
- Relay neurons
- Motor neurons
11
Q
What are sensory neurons?
A
- Bring messages from the peripheral nervous system to the central nervous system.
12
Q
What are relay neurons?
A
- Carry messages from one part of the CNS to another.
- They connect motor and sensory neurons.
- They also connect to other relay neurons.
13
Q
What are motor neurons?
A
- Carry messages from the CNS to the effectors in the body to execute a response.
14
Q
Sensory neurons have..
A
- Long dendrites
- Short axons
- A cell body within the axon
15
Q
Relay neurons have….
A
- Short dendrites
- Short axons
