Structure and Function of Neurons Flashcards
1
Q
What are neurons and what are they made up of?
A
- neurons are the cells that make up the nervous system
- they communicate w eachother using a mixture of electrical and chemical signals
- it is made up of the dendrites, cell body, myelin sheath, nodes of ranvier, axon and terminal button
2
Q
What is the function of dendrites?
A
- where nts receptors are found
- an electrical impulse occurs when nts and receptor binds
3
Q
What is the function of the cell body?
A
- includes nucleus which is the genetic material of the cell
4
Q
What is the function of the myelin sheath?
A
- protects axon
- helps to speed up electrical transmission of msg
5
Q
What is the function of the nodes of ranvier?
A
- speeds up electrical transmission by forcing impulse to jump across gaps along axon
6
Q
What is the function of the axon?
A
- sends a nerve impulse thru the neuron to transmit a message to the next neuron
7
Q
What is the function of the terminal button?
A
- located at the end of the neuron
- sends info thru to next neuron via nts
8
Q
What are the three types of neurons?
A
Sensory
Relay
Motor
9
Q
Describe the location, function and structure of sensory neuron
A
- located in PNS as clusters known as ganglia
- send info from senses (PNS) towards brain (CNS)
- receptors found in eyes, tongue and skin
- cell body in middle, long dendrites + short axons
10
Q
Describe the location, function and structure of relay neurons
A
- located in the CNS such as the brain
- they carry nerve impulses bw neurons allowing sensory + motor neurons to communicate
- they decide how to respond to sensations from these neurons
- they have no myelin sheath. short dendrites and short axons
11
Q
Describe the location, function and structure of motor neurons
A
- cell bodies located in CNS but long axons form part of PNS
- send info from brain/spinal cord (CNS) to effectors such as muscles/glands via long axons
- cell body at start, short dendrites and long axons