neurons Flashcards
(12 cards)
1
Q
what are neurons
A
cells that conduct electrical impulses and allow communication to occur
2
Q
what is the structure of a neuron
A
- consists of a cell body (stoma) whiich contains a necleus to store gentic code
- dendrites branch out from the cell body and carry electrical impulses to other neurons
- axons project away from cell body and carries signlas recieved by the dendrites to toher neurons
- myelin sheath is a white fatty substance which insulates the axon and speeds up the rate of conduction signals
- signal is carried away from cell body, down axon to its terminal, where the impulse can be transmitted to another neuron
3
Q
what are the 3 main types of neurons
A
- motor
- relay
- sensory
4
Q
what is the structure of a motor neuron
A
- short dendrites protrude durectly from the cell body
- impulse is carried away by a long axon to another terminal
5
Q
where are motor neurons located
A
- the cell body is inside the CNS
- axon is outside in the PNS
6
Q
what is the function of a motor neuron
A
controlls muscles and organs (effectors)
7
Q
what is the structure of a relay neuron
A
- short dendrites carry impulses to cwll body
- impulse carried away by a very short axon
8
Q
where are relay neurons located
A
the entire neuron is inside the CNS
9
Q
what is the function of a relay neuron
A
allows motor and sensory neurons to communicate
10
Q
what is the structure of a sensory neuron
A
- long dendrite carries impulse to cell body which is at the side of a short axon ( cell body has no dendrites)
11
Q
where are sensory neurons located
A
- in the PNS
- axon is in the CNS
12
Q
what is the function of a sensory neuron
A
carries nerve impulses from sensory receptors (eg: vison, touch) to the spinal cord and brain
