Chap 8: Nervous System WS Flashcards
Consists of the brain and spinal cord
CNS
Transmits action potentials from sensory organs to CNS.
Afferent Division
Nerves and ganglia outside the CNS
PNS
Subdivision of the efferent division that transmits action
potentials from the CNS to skeletal muscle only
Somatic motor nervous system
Subdivision of the efferent division that transmits action
potentials to smooth muscle, cardiac muscle, or glands; includes sympathetic and parasympathetic divisions
Autonomic nervous system
Location of the nucleus and source of information for protein
synthesis.
Cell body
Usually receives information and transmits it to the cell body
Dendrite
Areas of rough endoplasmic reticulum concentration in the cell
body
Nissl bodies
Branch of an axon
Collateral axon
Insulating layer of cells around an axon
Myelin sheath
Long cell process from the cell body; conducts action potentials
Axon
Neuron with several dendrites and one axon; most efferent
neurons
Multipolar
Neuron with one dendrite and one axon; found in the eye and
nose
Bipolar
Neuron with single process that functions as an axon and a
dendrite; most afferent neurons.
Unipolar
Produce and circulate cerebrospinal fluid in the CNS.
Ependymal cells
Participate with blood vessel endothelium to form a
permeability barrier in the CNS between blood and nerve cells
Astrocytes
Form myelin sheaths around axons in the PNS
Schwann cells
Form myelin sheaths around axons in the CNS
Oligodendrocytes
Help remove bacteria and cell debris from the CNS
Microglia
Axons are surrounded by the (1) of oligodendrocytes in the
(2) or Schwann cells in the (3) . (4) rest in indentations of
the oligodendrocytes or Schwann cells, whereas (5) have
cell processes repeatedly wrapped around them. In
myelinated axons, gaps in the myelin sheath called (6) can
be seen between the oligodendrocyte segments or between
Schwann cells.
- Cell processes
- CNS
- PNS
- Unmyelinated axons
- Myelinated axons
- Nodes of Ranvier
Gray matter on the surface of the brain
Cortex
Color of groups of neuron cell bodies and their dendrites
Gray matter
Cluster of gray matter located deep in the brain
Nucleus
Cluster of neuron cell bodies in the PNS
Ganglion
Color produced by bundles of axons with their myelin sheaths
White matter
Conduction pathway composed of white matter in the CNS
Nerve tract
Axon end that interacts with other neurons or effector organs
Postsynaptic membrane
Bundle of axons and its connective tissue sheath in the PNS
Nerves
Membrane of the dendrite or effector cell
Postsynaptic membrane
Space separating the presynaptic terminal and postsynaptic
membrane
Synaptic cleft
General term for chemical substances released from the
presynaptic terminal.
Neurotransmitters
Structures in which the neurotransmitter is stored
Synaptic vesicles
Condition in postsynaptic cell if potassium or chloride channels
open
Hyperpolarized
Most common neurotransmitters
Acetylcholine and norepinephrine
Enzyme that breaks down acetylcholine soon after its release
Acetylcholinesterase
Part of the peripheral nervous system with 12 pairs of nerves
Cranial
Part of the peripheral nervous system with 31 pairs of nerves.
Spinal
Fibers that collect information and carry it to the CNS
Afferent
Part of the central nervous system housed within the cranial
vault
Brain
Fibers that relay information from the CNS to various parts of
the body
Efferent
Part of the central nervous system from the foramen magnum
to the second lumbar vertebra
Spinal cord
Part of the neuron (nerve cell) that contains the nucleus; site of
general cell functions
Cell body
Part of the central nervous system containing the brainstem,
diencephalon, cerebrum and cerebellum
Brain
Receive action potentials and conduct them toward the cell
body
Dendrites
Conducts action potentials away from the cell body.
Axon
Support cells of the nervous system; function to nourish, protect
and insulate the neurons
Neuroglia
