Nervous System 1 Flashcards
(41 cards)
One of the two major control systems of the body mediating systemic homeostatic processesmuscle contractionintegration of blood oxygen, carbon dioxide, and pH levels via respiratory activityregulation of volumes and pressures in the circulation via cardiovascular and urinary functiondigestive system motility and secretion
Nervous System
______ system is a quick fix to homeostatic disturbance
Nervous system
____ system is slower long term maintenance
Endocrine system
What are the functional units of the nervous system?
Neurons
What are the support cells of neurons?
Neuroglia
Nervous system uses a combo of ____ and _____ to communicate info around body
chemical and electrical signals
_____ are stimulated by environmental changes or the activities of other cells
Dendrites
____ contains the nucleus and mitochondria, and other organelles and inclusions
Cell body
____ conducts nerve impulse toward synaptic terminals
Axon
_____ are clusters of ribosomes in cell body
Nissl Bodies
______ affect another neuron or effector organ
Synaptic terminals
_____ are clusters of myelin
Internodes
____ are formed by neuroglial cells
Internodes
____ form myelin for axons in CNS
Oligodendrocytes
____ form myelin for axons in PNS
Schwann cells
Internodes separated by small segments of axon not covered in myelin called ______Function: Speed up the rate of nerve impulse conduction (Saltatory conduction)
Nodes of Ranvier
(pseudounipolar neurons, bipolar)Afferent division of PNSCarry sensory information from reflex receptor to CNSDendrites/Cell body in PNSAxons typically myelinated and extend into CNS
Sensory Neurons
(Multipolar neurons)Efferent division of PNSCarry motor commands from CNS to EFFECTORSDendrites/Cell body in CNSAxons typically myelinated, extend into PNS and synapse with effectors
Motor Neurons
(Multipolar, Anaxonic)Found only in the CNSCarry information from one neuron to anotherIntegration
Interneurons
Always the same (depolarization followed by repolarization) with no change in strength or size as they travel along the membrane–All-or-none –Triggered at Axon Hillock when Threshold Potential reached (Vm at which AP triggered; typically around -50mV))–Always propagates along cell membrane of axon from axon hillock toward axon terminals –Relatively fast changes in Vm
Action potential
(Vm at which AP triggered; typically around -50mV))
Threshold Potential
–Small changes in membrane potential of variable strength/amplitude –Only travel a short distance along membrane and lose strength as they travel–Often last longer than APs; Ex. IPSP and EPSP
Graded Potentials (GP):
(depolarizations); moves Vm towards threshold potential; increases likelihood of AP
EPSPs. Excitatory postsynaptic potentials
(hyperpolarizations); moves Vm away from threshold; decreases likelihood of AP
IPSPs. Inhibitory postsynaptic potentials