The Nervous System Flashcards
Axon
Neuron process that carries impulses away from the nerve cell body
Afferent neuron
Nerve cells that carry impulses toward the central nervous system
Central nervous system
The brain and spinal cord
Cerebral hemisphere
What the brain is formed out of…. Two
Dendrites
The branching extensions of neurons that carry electrical signals to the cell body
Efferent neuron
Neurons that conduct impulses away from the central nervous system
Gray matter
The gray area of the central nervous system; contains unmyelinated nerve fibers and nerve cell bodies
Meninges
The membranes that cover the brain and spinal cord.
Nerve
Bundle of neuron processes outside the central nervous system
Neurons
Cells of the nervous system specialized to transmit messages throughout the body
Peripheral nervous system
A system of nerves that connects the outlying parts of the body with the central nervous system
Polarization
The state of an unstimulated neuron or muscle cell in which the inside of the cell is relatively negative in comparison to the outside
Reflex
Automatic reaction to a stimulus
Somatic nervous system
A division of the peripheral nervous system, also called the voluntary nervous system
White matter
White substance of the central nervous system, the myelinated nerve fibers
Autonomic nervous system
The division of the nervous system that functions involuntarily
Brain stem
The portion of the brain consisting of the medulla, pons, and midbrain
Cerebellum
Part of the hindbrain, involved in producing smoothly coordinated skeletal muscle activity
Cerebrospinal fluid
The fluid produced in the cerebral ventricles; fills the ventricles and surrounds the central nervous system
Depolarization
The loss of a state of polarity; the loss of a negative charge inside the plasma membrane
Ganglion
A group of nerve cell bodies located in the peripheral nervous system
Interneurons
Also called association neurons; completes the pathway between afferent and efferent neurons
Myelin
A white, fatty lipid substance
Neuroglia
The nonneuronal tissue of the central nervous system that performs supportive and other functions
Nodes of Ranvier
a gap in the myelin sheath of a nerve, between adjacent Schwann cells.
Plexus
A network of interlacing nerves, blood vessels, or lymphatics
Receptor
A peripheral nerve ending specialized for response to particular types of stimuli
Repolarization
the change in membrane potential that returns the membrane potential to a negative value after the depolarization phase of an action potential has just previously changed the membrane potential to a positive value
Synapse
The region of communication between neurons
