Cells of the Nervous System and Neurotransmitters at Synapses Unit 3 Flashcards
Name the two types of cell that make up the nervous system
Nerve cells (neurons) and glial cells
Name the three types of neurons in the body
- Sensory
- Inter
- Motor
What are the 3 basic parts to the neurons ?
- Dendrite
- Cell body
- Axon
What is the function of the dendrite ?
Receive nerve impulse and pass them towards the cell body
What two parts are found in the cell body of the neuron ?
The cytoplasm and nucleus
What is the function of the axon ?
A single nerve fibre that carries nerve impulses away from the cell body
What name is given to the layer of fatty material that surrounds an axon ?
Myelin sheath
What process lays down the myelin sheath from before birth to adolescence ?
Myelination
What name is given to a nerve fibre that is lacking a myelin sheath ?
Unmyelinated fibre
What is the purpose of the myelin sheath ?
To greatly increase the speed at which nerve pulses pass
Name an autoimmune disease that breaks down the myelin sheath ?
Multiple sclerosis
Why is a baby unable to regulate their own body temperature until they are about 6 months old ?
The hypothalamus that controls the temperature is not fully myelinated yet
Why are infants not able to control their full lower body until about 2 years old ?
The neurons that lead to the lower body are not fully myelinated yet
What is the purpose of glial cells in the nervous system ?
To physically support the neurons and carry out myelination
What name is given to the tiny space between the axon ending of one nerve and the dendrite of the next neuron ?
Synapse or synaptic cleft
What name is given to the neuron before a synapse ?
A presynaptic neuron
What name is given to a neuron after a synapse ?
A postsynaptic neuron
Name the type of chemical messenger relayed across the synapse from neuron to neuron ?
Neurotransmitter
Name three neurotransmitters
- Acetylcholine
- Noradrenaline
- Dopamine
What structures are found in each synaptic terminal (axon ending) that contain neurotransmitter ?
Vesicles