Lecture 9: Nervous System Flashcards
What are the functions of the nervous system?
1) sense and respond to internal and external stimuli
2) information processing
3) transmit signals between brain and body to control body movement
Neuron vs Nerve?
a neuron is a nerve cell and a nerve is a bundle of neurons
Ganglia?
clusters of neurons forming simple processing centers located in the peripheral nervous system
Brain?
clusters of neurons forming higher order processing centers to integrate information: located in the central nervous system
Glial cells?
provide physical and metabolic support for neurons
Explain the neuron and its parts
the neuron is the fundamental unit of the nervous system.
cell body of the neuron contains most of its organelles including the nucleus
the dendrite are highly branched extensions that receive signals from other neurons
the axon is a single extension that transmit signals to other neurons
Explain the “smaller” parts of the neuron
myelin sheath: insulation around some axons to prevent signal from disappearing as it moves along; it is made by glial cells
mode of ranvier: gaps in the myelin sheath
signal flow: a signal from another neuron is received at the?
dendrites
signal flow: the electrical signal is sent down the axon towards the?
synaptic terminal
what is a synapse?
space between two neurons
What is a neurotransmitter?
chemical messengers
signal flow: information is sent across the — in the form of — from the axon of the — to the dendrites of the —
synapse, neurotransmitters, presynaptic cell, postsynaptic
signal flow: the signal then moves through the next?
neuron in a similar pattern
What are the 3 types of actions a neurotransmitter can produce?
excitatory, inhibitory, and modulatory
excites the neuron and cause it to “fire off the message” (message continues to be passed along to the next cell) example: epinephrine/adrenaline
