Cells Of The Nervous Stystems And Synapses 3.4 Flashcards
What are the three types of neurons
Sensory
Inter
Motor
What are the four structures of a neuron
Cell body
Dendrite
Axon
Myelin sheath
What is the function of the cell body
Contains the nucleus and most of the cytoplasm
What is the function of the dendrite
Nerve fibres that receive nerve impulses and pass them towards a cell body
What is the function of the axon
Single nerve fibre that carries nerve impulses away from the cell body
What is the myelin sheath
A layer of fatty material that insulates the axon
Why is insulating the axon important
To increase the speed of electrical impulses and for extra protection
What is myelination
The development of the myelin sheath
How long does it take for the myelin sheath to fully develop
From birth to adolescence
What do glial cells do
Some produce the myelin sheath and others support the neurons
What are neurotransmitters
Chemicals
How do you remove extra neurotransmitters from the synaptic cleft
Enzyme degradation and reuptake
What is enzyme degradation
Neurotransmitters are broken down by enzymes
What is reuptake
Neurotransmitters are taken back up directly by the pre synaptic membrane and put back into vesicles
What are endorphins
Neurotransmitters that stimulate neurons involved in reducing intensity of pain by binding to receptors which blocks the pain signal