CHAPTER 12 NERVOUS SYSTEM/NERVOUS TISSUE |THE
SMART WAY TO PASS | REAL TESTS, REAL RESULTS!
Nervous system basic function Answer: Gathers information, interprets it, and produces
responses to internal and external stimuli.
Three basic functions of the nervous system Answer: Sensation, integration, and response.
Sensation Answer: Detection of internal or external stimuli by sensory receptors.
Integration Answer: Processing and interpreting sensory information to decide what should
happen next.
Response Answer: Action produced by effectors such as muscles or glands.
Central nervous system (CNS) Answer: Brain and spinal cord.
Peripheral nervous system (PNS) Answer: All nervous tissue outside the CNS, including nerves
and ganglia.
Gray matter Answer: Nervous tissue mostly containing neuron cell bodies, dendrites, axon
terminals, and synapses.
White matter Answer: Nervous tissue mostly containing myelinated axons that connect gray
matter regions.
Nucleus in the CNS Answer: Cluster of neuron cell bodies in the CNS with a localized
function.
Ganglion Answer: Cluster of neuron cell bodies in the PNS.
Tract Answer: Bundle of axons in the CNS.
Nerve Answer: Bundle of axons in the PNS.
Optic nerve Answer: Structure extending from the eye to the optic chiasm.
Optic chiasm Answer: Crossing point of optic nerve fibers and border between peripheral and
central visual pathways.
Optic tract Answer: Bundle of visual fibers that extends from the optic chiasm toward the brain.
Somatic nervous system Answer: Functional division for conscious perception, voluntary
skeletal muscle control, and some reflexes.
Autonomic nervous system Answer: Functional division for involuntary control of smooth
muscle, cardiac muscle, and glands to maintain homeostasis.
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, Enteric nervous system Answer: Nervous system division within the digestive tract that can
function independently but communicates with the CNS.
Neuron Answer: Excitable nervous tissue cell that transmits electrical and chemical signals.
Glial cell Answer: Supporting nervous tissue cell that protects, supports, nourishes, or insulates
neurons.
Soma or cell body Answer: Main part of a neuron containing the nucleus and organelles.
Dendrite Answer: Reception region of a neuron that receives signals from other cells.
Axon Answer: Secretory/conducting region that carries impulses away from the cell body
toward target cells.
Axon hillock Answer: Cone-shaped region where the axon begins and where action potentials
are often initiated.
Axon terminal or synaptic end bulb Answer: End of an axon that releases neurotransmitter.
Synapse Answer: Connection between a neuron and its target cell, including the presynaptic
element, synaptic cleft, and postsynaptic membrane.
Synaptic cleft Answer: Small gap between presynaptic and postsynaptic cells where
neurotransmitter diffuses.
Myelin Answer: Insulating layer around axons made by oligodendrocytes in the CNS and
Schwann cells in the PNS.
Node of Ranvier Answer: Gap in the myelin sheath where voltage-gated channels are
concentrated and action potentials jump during saltatory conduction.
Sensory neuron Answer: Neuron that carries information from sensory receptors toward the
CNS.
Motor neuron Answer: Neuron that carries commands away from the CNS to muscles or
glands.
Interneuron Answer: Neuron located within the CNS that processes information between
sensory and motor pathways.
Unipolar neuron Answer: Neuron with one process that functions as both dendrite and axon,
common in sensory neurons of the PNS.
Bipolar neuron Answer: Neuron with one dendrite and one axon, found in special senses such
as retina, olfactory epithelium, and inner ear.
APPHIA – Crafted with Care and Precision for Academic Excellence.
2
SMART WAY TO PASS | REAL TESTS, REAL RESULTS!
Nervous system basic function Answer: Gathers information, interprets it, and produces
responses to internal and external stimuli.
Three basic functions of the nervous system Answer: Sensation, integration, and response.
Sensation Answer: Detection of internal or external stimuli by sensory receptors.
Integration Answer: Processing and interpreting sensory information to decide what should
happen next.
Response Answer: Action produced by effectors such as muscles or glands.
Central nervous system (CNS) Answer: Brain and spinal cord.
Peripheral nervous system (PNS) Answer: All nervous tissue outside the CNS, including nerves
and ganglia.
Gray matter Answer: Nervous tissue mostly containing neuron cell bodies, dendrites, axon
terminals, and synapses.
White matter Answer: Nervous tissue mostly containing myelinated axons that connect gray
matter regions.
Nucleus in the CNS Answer: Cluster of neuron cell bodies in the CNS with a localized
function.
Ganglion Answer: Cluster of neuron cell bodies in the PNS.
Tract Answer: Bundle of axons in the CNS.
Nerve Answer: Bundle of axons in the PNS.
Optic nerve Answer: Structure extending from the eye to the optic chiasm.
Optic chiasm Answer: Crossing point of optic nerve fibers and border between peripheral and
central visual pathways.
Optic tract Answer: Bundle of visual fibers that extends from the optic chiasm toward the brain.
Somatic nervous system Answer: Functional division for conscious perception, voluntary
skeletal muscle control, and some reflexes.
Autonomic nervous system Answer: Functional division for involuntary control of smooth
muscle, cardiac muscle, and glands to maintain homeostasis.
APPHIA – Crafted with Care and Precision for Academic Excellence.
1
, Enteric nervous system Answer: Nervous system division within the digestive tract that can
function independently but communicates with the CNS.
Neuron Answer: Excitable nervous tissue cell that transmits electrical and chemical signals.
Glial cell Answer: Supporting nervous tissue cell that protects, supports, nourishes, or insulates
neurons.
Soma or cell body Answer: Main part of a neuron containing the nucleus and organelles.
Dendrite Answer: Reception region of a neuron that receives signals from other cells.
Axon Answer: Secretory/conducting region that carries impulses away from the cell body
toward target cells.
Axon hillock Answer: Cone-shaped region where the axon begins and where action potentials
are often initiated.
Axon terminal or synaptic end bulb Answer: End of an axon that releases neurotransmitter.
Synapse Answer: Connection between a neuron and its target cell, including the presynaptic
element, synaptic cleft, and postsynaptic membrane.
Synaptic cleft Answer: Small gap between presynaptic and postsynaptic cells where
neurotransmitter diffuses.
Myelin Answer: Insulating layer around axons made by oligodendrocytes in the CNS and
Schwann cells in the PNS.
Node of Ranvier Answer: Gap in the myelin sheath where voltage-gated channels are
concentrated and action potentials jump during saltatory conduction.
Sensory neuron Answer: Neuron that carries information from sensory receptors toward the
CNS.
Motor neuron Answer: Neuron that carries commands away from the CNS to muscles or
glands.
Interneuron Answer: Neuron located within the CNS that processes information between
sensory and motor pathways.
Unipolar neuron Answer: Neuron with one process that functions as both dendrite and axon,
common in sensory neurons of the PNS.
Bipolar neuron Answer: Neuron with one dendrite and one axon, found in special senses such
as retina, olfactory epithelium, and inner ear.
APPHIA – Crafted with Care and Precision for Academic Excellence.
2
