Chapter 45: Nuerons and Nervous System Flashcards
dendrites
receive information from other neurons
cell body
contains the nucleus and most of the cell organelles
axon
conducts action potentials away from the cell body
axon terminals
synapse with a target cell
synapse
axon terminal comes extremely close to the membrane of the target cell
neurotransmitter
chemical messengers
oligodendrocytes
wrap around axons of neurons of brain and spinal cord, covering them with concentric layers of insulating plasma membrane
schwann cells
outside brain and spinal cord, wrap axons
myelin
covering produced by the oligodendrocytes and schwann cells. Give glistening white appearance
Astrocytes
contribute to the blood-brain barrier
blood-brain barrier
protects the brain from toxic chemicals in the blood
tripartite synapse
idea that a synapse includes not only the pre- and postsynaptic neurons but also connections from astrocytes
microglia
provide the nervous system with immune defenses
membrane potential
is a charge difference across the membrane. with the inside of cell negative relevant to outside
resting potential
steady state membrane potential
voltage
force that causes electrically charged particles to move from one point to another
sodium potassium pump
keeps the concentration of K+ greater on the outside. requires ATP to do work