nervous system pt 2 - unit 4 Flashcards
white colored nervous tissue. made of myelinated axons
white matter
gray-colored nervous tissue. made of dendrites/cell bodies/short (unmyelinated) axons.
gray matter
two types of matter of nervous tissue
gray and white
bundles of myelinated axons in CNS
tracts
bundles of myelinated axons in PNS
nerves
pockets of gray matter in CNS
nucleus
pockets of gray matter in PNS
ganglion
electrical charge within a neuron when its at rest is -70 mV
resting membrane potential
are cytoplasm of neurons neg or pos charged. this is because of proteins, nucleic acids, and phosphates in it.
negative
most abundent positive ion within cell
K+
two most abundent ions outside cell
Na+ and Cl-
use energy from ATP breakdown to force ions across PM
pumps
from pores on PM. allow materials to pass through.
channels
open/form pore in response to a stimuli: ____ channel
gated channel
3 grated channels
mechanically, ligand, voltage
type of grated channel. open in response to pressure/stretch. found in PM of dendrties of sensory neurons
mechanically gated channel
type of grated channel. open in response to chemicals binding to them. found in PM of dendrites and cell bodies.
ligand gated channels
type of grated channel. open in response to specific charge/voltage in cytoplasm. found in PM of axon/ axon terminals
voltage gated channels.
3 ways the electrical charge can change within a neuron
deporalization, hyperalization, repolarization
charge change: charge in neuron becomes more positive
deporalization
charge change: change in neuron becomes more negative
hyperalization
charge change. when a depolarized/hypolarized cells returns to normal at -70 mV
repolarization
movement of charged particles down the length of cell
electricity in body
mechanically/ligand-gated channels open in dendrites/cell bodies of neurons.
cause deporalization
axons contain _____ gated Na+ channels that open at -55mV down the length of PM
voltage
when region of neuron (or muscle cell) axon quickly depolarizes via opening of voltage gated channels followed by repolarization from opening of VG K+ channels.
action potential
VGK+ channels open at
+30mV
signaling molecules released from neurons (axon terminals) into synapse. they are small protein molecules / modified amino acids.
neurotransmitters
formation of new neurons. occurs during child development.
neurogenesis
the repair of axons along damaged myelinated in PNS
neural regeneration
drugs that prevent axon from firing
channel blockers
drugs that mimic neurons/neurotransmitters
agonists
drugs that act as receptor blockers
antagonists
drugs that bind and block enzymes in synapse
enzyme inhibitor
drugs that block NT reuptake proteins
reuptake inhibitors
Step ___: NT diffuse across synapse, bind to receptors
1
step ___: NT diffuses out of synapse and neuroglia break it down
2
step ___: NT reuptake. removes NT from synpase and recycles it.
3
step ____: enzyme breaks down NT
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