Flashcards in Nervous System Deck (110)
location of nucleus, ER, ribosomes
appendages from soma that received incoming signals from other cells
-integrates incoming signals from dendrites
-plays key role in initiation of APs by summing inhibitory and excitatory signals from dendrites
-insulate axons to prevent signal loss/crossing of signals
-maintains electric signal in neuron
-increases speed of conduction
-made of lipids (poor conductor of electricity)
-produce myelin in the CNS
-can myelinate multiple neurons at once
-produce myelin in the PNS
-can only myelinate one neuron at once
space between neurons containing the synpatic cleft, nerve terminal, and postsynaptic membrane
multiple neurons bundled together in the PNS
-structures containing cell bodies of neurons and glial cells
-function like relay stations - one nerve enters and the other exits
-bundles of axons in the CNS
-only carry one type of information
group of cell bodies in the same tract
-non-neuronal cells in both the CNS and PNS
-function in myelin formation, supporting neurons, and providing nutrients to neurons
-form blood-brain barrier -- controls the transmission of solutes from bloodstream into nervous tissue
-line ventricles of the brain
-produce cerebrospinal fluid which physically supports the brain and acts as shock absorber
phagocytic cells that ingest and break down waste products and pathogens in CNS
-net electric potential difference that exists across cell membrane
- -70 mV
-more negative inside the cell than the outside
What is the concentration of K+ inside the cell?
What is the concentration of K+ outside the cell?
What is the equilibrium potential of K+?
Potassium Leak Channels
allow slow leak of K+ outside the cell
Is the cell more permeable to K+ or Na+?
What is the concentration of Na+ inside the cell?
What is the concentration of Na+ outside the cell?
Sodium Leak Channels
slow leak of Na+ into the cell
What is the equilibrium potential of Na+?
pumps 3 Na+ out of cell and 2 K+ into cell
-ranges from -55mV to -40mV
-reached when the axon hillock receives enough excitatory input and an AP is triggered
-multiple signals integrated during short period of time
-number of small excitatory signals firing at nearly the same moment
-additive effects are based on the number and location of the incoming signals
-large number of inhibitory signals firing directly on soma cause more hyperpolarization of axon hillock than depolarization caused by few excitatory signals on dendrites