Nervous System Flashcards
Nervous System
The master controlling and communication system in the body.
Sensory Input
Gathered information about a stimulus.
Integration
Processes and interprets sensory input and makes decisions.
Motor Output
Activated muscles or glands from integration center.
Central Nervous System (CNS)
Consists of brain and spinal cord. Integration and command center for nervous system.
Peripheral Nervous System (PNS)
Links CNS to rest of body through nerves.
Sensory (afferent) Division
Convey impulses to CNS from sensory receptors.
Motor (efferent) Division
Carries impulses from CNS to effector muscles and organs.
Somatic Nervous System
Voluntary controls skeletal muscles.
Autonomic Nervous System
Regulates involuntary processes in the body.
Neuroglia
Support, insulate, and protect neurons. “nerve glue”
Astrocytes
Star shaped, cling to neurons to brace and anchor them to nutrient supply lines.
Microglia
Spiderlike, dispose of debris and bacteria.
Ependymal Cells
Circulates cerebrospinal fluid in the brain.
Oliodendrocytes
Wrap around nerve fibers to produce myelin sheaths.
Schwann Cells
Form myelin sheaths in PNS.
Neuron
Highly specialized cells used to transmit messages throughout the body.
Synapse
Functional nerve junction.
Myelin Sheath
Encloses Axon.
Nodes of Ranvier
Gaps in Schwann cells.
Gray Matter
Unmyelinated fibers.
Polarized
Fewer positive ions.
Depolarized
Inward rush of sodium reverses polarization.
Action Potential
Long distance signal transmitted by a neuron.
Repolarization
Outflow of positive ions brings neuron back to resting stage.
Reflexes
Rapid, predictable, involuntary responses to stimuli.
Autonomic Reflexes
Regulate activity of smooth muscles, heart, and glands.
Receptor
Gathers stimulus.
Effector
Reaction to stimulus.
Association Neuron
Connects motor and sensory neurons.
