AP Biology Neuron Flashcards

5867104266	dendrites	Branchlike parts of a neuron that are specialized to receive information.	0
5867104267	axon	A threadlike extension of a neuron that carries nerve impulses away from the cell body.	1
5867104268	myelin sheath	A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.	2
5867104269	Schwann cells	Supporting cells of the peripheral nervous system responsible for the formation of myelin.	3
5867104270	depolarization	The process during the action potential when sodium is rushing into the cell causing the interior to become more positive; voltage change that occurs when the difference in charge across a membrane decreases	4
5867104271	terminal branch	Branched endings of an axon that transmit messages to other neurons	5
5867104272	nodes of ranvier	Gaps in the myelin sheath to which voltage-gated sodium channels are confined; Gaps in the myelin sheath of the axons of peripheral neruons. Action potentials can 'hump' from node to node, thus increasing the speed of conduction (saltatory conduction).	6
5867104273	cell body	Largest part of a typical neuron; contains the nucleus and much of the cytoplasm	7
5867104274	membrane potential	a difference in electrical charge between the cytoplasm (negatively charged) and the extracellular fluid (positively charged)	8
5867104275	polarized state	(resting potential) a neuron in its unstimulated state	9
5867104276	-70mV	a neuron in is polarized state has a membrane potential of ________	10
5867104277	sodium-potassium pump	a carrier protein that uses ATP to actively transport sodium ions out of a cell and potassium ions into the cell, maintaining neuron polarization	11
5867104278	resting potential	in order for the nerve to fire, a stimulus must be strong enough to overcome the _________	12
5867104279	gated-ion channel	A channel in the plasma membrane for one specific ion, such as sodium or calcium; in the terminal branch of a neuron, it is responsible for the release of neurotransmitter into the synapse	13
5867104280	sodium-ion channel	when stimulated, the result is a decrease in polarization to about -60mV	14
5867104281	hyperpolarization	The movement of the membrane potential of a cell away from rest potential in a more negative direction.	15
5867104282	action potential	A neural impulse; a brief electrical charge that travels down an axon. The action potential is generated by the movement of positively charged atoms in and out of channels in the axon's membrane.	16
5867104283	calcium-gated channels	important for neurotransmitters	17