Chapter 7: Nervous System Flashcards
Axon
Neuron process that carries impulses away from the nerve cell body ; efferent process; the conducting portion of a nerve cell
Afferent Neuron
Nerve cells that carry impulses toward the central nervous system
Autonomic Nervous System
The division of the nervous system that functions involuntarily; innervates cardiac muscle, smooth muscle, and glands
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 hindbrain ; involved in producing smoothly coordinated skeletal muscle activity
Cerebral Hemisphere
Half of the cerebrum , the part of brain that controls muscle functions and emotions
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
Depolarization
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
Neuroglia
The non neuronal 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
Constrictions in the myelin sheath that surrounds the axons of nerve cells
Peripheral Nervous System
Consist of the nerves and ganglia outside of the brain and spinal cord
Plexus
Complex network of nerves, blood vessels, or lymphatic vessels
Polarization
Maintaining an excess of sodium ions on the outside and an excess of potassium ions on the inside
Receptor
A molecule on the surface or within the cell that I recognizes and binds with specific molecules
Reflex
A rapid, involuntary response to a stimulus
Repolarization
The return of ions to their previous resting state
Somatic Nervous System
Part of the peripheral nervous system associated with skeletal muscle voluntary control of body movements. Consist of afferent and efferent nerves
Synapse
A structure that permits a neuron to pass an electrical or chemical signal to another cell
White Matter
Tissue found in the brain , contains nerve fibers
