structure and function of neurons Flashcards
1
Q
Structure of neurons
A
- dendrites
- cell body
- axon
- myelin sheath
- nodes of ranvier
- terminal button
MUST DRAW AND LABEL = 6m
2
Q
Dendrites
A
- post synaptic membrane
- where neurotransmitter receptors found
- receptor and neurotransmitter bind
- causes new electrical impulse
3
Q
Cell body
A
- includes nucleus
- contains genetic material
4
Q
Axon
A
- sends nerve impulse (action potential) through neuron
- to transmit message to next neuron
5
Q
Myelin sheath
A
- protect axon
- helps speed up transmission of message
6
Q
Nodes of Ranvier
A
- gap
- speed up transmission of impulse
- by forcing it to ‘jump’ across the gaps
- along axon
7
Q
Terminal button
A
- pre synaptic membrane
- end of neuron
- send information through to next neuron
-release neurotransmitters
8
Q
Location of sensory neurons
A
- found in PNS
- in clusters known as ganglia
9
Q
Function of sensory neurons
A
- send info from senses (PNS)
- towards brain (CNS)
- receptors found in eyes, skin, tongue
10
Q
Structure of sensory neurons
A
- long dendrites = cover long surface area
- short axon = only send info from PNS to CNS
11
Q
Location of relay neurons
A
- found in CNS
- brain and visual system
12
Q
Function of relay neurons
A
- carry nerve impulses between neurons
- allow sensory and motor neurones to communicate
- analyse sensations from these neurons
- decide how to respond
13
Q
Structure of relay neurons
A
- short axon = not far for message to travel
- short dendrites = only small SA to cover and only attached to one sensory neuron
- no myelin sheath = not need speeding up only from one neuron to another
14
Q
Location of motor neurons
A
- cell bodies found in CNS
- long axons part of PNS
15
Q
Function of motor neurons
A
- send info via long axons
- from brain/spinal cord (CNS) to muscle/gland (effector)
