Chapter 3 Flashcards
Neurons
cells in nervous system that communicate with each other to perform information processing tasks
Cell Body
coordinates information - processing tasks and keeps cell alive
Dendrites
receive info from other neurons and relay to cell body
Axon
carries info through neuron to other neurons, or muscle glands
Myelin Sheath
insulating layer on axon
glial cells
support cells in neurons system (make up myelin sheath, allow for faster/more efficient info transfer)
sensory neurons
receive info from world and convey to brain via spinal cord (light sound taste touch)
motor neurons
carry signals from spinal cord to muscles
interneurons
connect sensory, motor, or other interneurons
resting potentials
difference in charge inside and outside of cell
K+ and A- more abundant inside
Na+ more abundant outside
action potential
electrical signal conducted along length of axon to a synapse
(all or nothing, either threshold to start action potential is met or not (not difference it strengths))
-Na+ flows in and increases charge in inside
-influx of Na+ caused more channels to open and keeps action potential going
refractory period
time following action potential when new action potential can’t be initiated
- Na+ channels close
- K+ channels open and K+ flows out to restore internal negative charge
-pumps push out Na+ and take in K+ to restore ion balance
terminal buttons
end of axons, filled with neruotranmitters
neurotransmitter
chemical that transmit info to receiving dendrites
receptors
parts of cell membrane that receive neurotransmitters to active or prevent new electrical signal
three possibilities in synpase
neurotransmitters…
1. absorbed by terminal buttons on cell it just came from (reuptake)
2. broken down by enzymes
3. drift away
agonistic
increase action of neurotranmitters
antagonistic
diminish function of neurotranmitters
central nervous system
brain and spinal cord
receive info from external world and processes/coordinates, send to to skeletal and muscular systems
peripheral nervous system
connects central ns to body’s organs and muscles
somatic pns
set of nerves that convey info between voluntary muscles and central ns
autonomic pns
set of nerves that carry involuntary and automatic commands to blood vessels