Chapter 7 Flashcards
Autonomic Nervous System
The division of the nervous system that functions involuntarily; innervates cardiac muscle, smooth muscle, and glands.
Afferent Neuron
Nerve cells that carry impulses toward the central nervous system.
Axon
Neuron process that carries impulses away from the nerve cell body; efferent process; the conducting portion of a nerve cell.
Brain Stem
The portion of the brain consisting of the medulla, pons, and midbrain.
Central Nervous System
The brain and the spinal cord.
Cerebellum
Part of the hind-brain; involved in producing smoothly coordinated skeletal muscle activity.
Cerebral Hemisphere
Highest level of the Central Nervous System; divided into right and left hemisphere.
Cerebrospinal Fluid
The fluid produced by choroid plexuses; fills the ventricles and surrounds the central nervous system.
Dendrites
The branching extensions of neurons that carry electrical signals to the cell body; the receptive portion of a nerve cell.
Deplorization
The loss of a state of polarity; the loss of a negative charge inside the plasma membrane.
Efferent Neuron
Neurons that conduct impulses away from the central nervous system.
Ganglion
A group of nerve cell bodies located in the peripheral nervous system.
Gray Matter
The gray area of the central nervous system; contains unmyelinated nerve fibers and nerve cell bodies.
Interneurons
Completes the pathway between afferent and efferent neurons; also called an association neuron.
Meninges
The membranes that cover the brain and spinal cord.
Myelin
A white, fatty lipid substance.
Nerve
Bundle of neuronal processes (axons) outside the central nervous system.
Neurolgia
The nonneuronal tissue of the central nervous system that performs supportive and other functions; also called glia.
Neurons
Cells of the nervous system specialized to transmit messages throughout the body.
Nodes of Ranvier
Periodic gap in the insulating sheath on the axon of certain neurons that serves to facilitate the rapid conduction of nerve impulses.
Peripheral Nervous System
A system of nerves that connects the outlying parts of the body with the central nervous system.
Plexus
A network of interlacing nerves, blood vessels, and lymphatics.
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; the resting state.
Receptor
A peripheral nerve ending specialized for response to particular types of stimuli.
Reflex
Automatic reaction to a stimulus.
Repolarization
Restoration of the membrane potential to the initial resting (polarized) state.
Somatic Nervous System
A division of the peripheral nervous system; also called the voluntary nervous system.
Synapse
The region of communication between neurons, or a neuromuscular junction between a neuron and a muscle cell.
White Matter
White substance of the central nervous system; the myelinated nerve fibers.
