Why is nervous system needed
Neurons
Anatomy of a neuron
Soma
Dendrites
Axon
Synapses
connection between neurons
how many neurons in human brain
100 billion
What does neurotransmitter removal ensure
that nervous system signalling is rapid and dynamic
how many mechanisms - removal of neurotransmitter from synapse
3
neurotransmitters can be returned to axon terminals for reuse or transported into glial cells
enzymes inactivate them
can diffuse out of the synaptic cleft
Divergence of signal
synapse expands signals throughout the nervous system
Convergence of signal
synapse expand signals specifically down a certain nerve tract
Afferent neurons (incoming neurons)
Efferent neurons
Interneurons
What is withdrawal reflex
Nerve net
Nervous system
Ganglia
paired or grouped neurons
ganglion
singular neuron
Function of glial cells