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BIO 2331 Unit 3 Study Guide Questions with
Verified Solutions 100% Correct Questions
and Correct Answers
Sensory input Ans: — Information gathered by sensory receptors
about internal and external changes
Integration Ans: — Processing and interpretation of sensory input
Motor output Ans: — Activation of effector organs/tissues
produces a response
Central nervous system (CNS) Ans: — Brain and spinal cord
Peripheral nervous system (PNS) Ans: — All nervous structures
outside of CNS
Sensory (afferent) division Ans: — Carries sensory information
towards CNS
Motor (efferent) division Ans: — Carries motor output from CNS to
effectors
Somatic nervous system Ans: — Voluntary control of skeletal
muscles
Autonomic nervous system Ans: — Regulates smooth muscle,
cardiac muscle, and glands
Sympathetic division Ans: — Produces survival effects such as
increased heart rate and breathing rate
Parasympathetic division Ans: — Produces resting effects such as
decreased heart rate and breathing rate
Neuroglia Ans: — Supporting cells in the nervous system
Astrocytes Ans: — Regulate substances entering the CNS from the
blood
Microglia Ans: — Specialized macrophages that phagocytize dead
tissue and foreign substances
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Oligodendrocytes Ans: — Form myelin sheath on axons in the CNS
Schwann cells Ans: — Form myelin sheath on axons in the PNS
Neuron Ans: — Transmits electrical signals
Dendrites Ans: — Receive signals coming into the neuron
Axon Ans: — Long projection that carries action potentials
Nerve Ans: — Bundle of many axons in the PNS
Tract Ans: — Bundle of many axons in the CNS
Nucleus Ans: — Bundle of neuron cell bodies in the CNS
Ganglion Ans: — Bundle of neuron cell bodies in the PNS
Myelin sheath Ans: — Insulates and electrically insulates axons
Node of Ranvier Ans: — Gap between myelin sheaths where action
potentials are generated
Multipolar neuron Ans: — Neuron with many dendrites and one
axon
Bipolar neuron Ans: — Neuron with one dendrite and one axon
Unipolar neuron Ans: — Neuron with one process that acts as both
the dendrite and axon
Voltage Ans: — Measure of the potential energy generated by
separation of different charges
Current Ans: — Flow of electrical charge between two points
Resistance Ans: — Hindrance to charge flow
Leakage channel Ans: — Always open, allows ions to diffuse down
electrochemical gradient
Ligand-gated channel Ans: — Opens with binding of a specific
chemical
Voltage-gated channel Ans: — Opens and closes in response to
changes in membrane potential
© 2025 All rights reserved
BIO 2331 Unit 3 Study Guide Questions with
Verified Solutions 100% Correct Questions
and Correct Answers
Sensory input Ans: — Information gathered by sensory receptors
about internal and external changes
Integration Ans: — Processing and interpretation of sensory input
Motor output Ans: — Activation of effector organs/tissues
produces a response
Central nervous system (CNS) Ans: — Brain and spinal cord
Peripheral nervous system (PNS) Ans: — All nervous structures
outside of CNS
Sensory (afferent) division Ans: — Carries sensory information
towards CNS
Motor (efferent) division Ans: — Carries motor output from CNS to
effectors
Somatic nervous system Ans: — Voluntary control of skeletal
muscles
Autonomic nervous system Ans: — Regulates smooth muscle,
cardiac muscle, and glands
Sympathetic division Ans: — Produces survival effects such as
increased heart rate and breathing rate
Parasympathetic division Ans: — Produces resting effects such as
decreased heart rate and breathing rate
Neuroglia Ans: — Supporting cells in the nervous system
Astrocytes Ans: — Regulate substances entering the CNS from the
blood
Microglia Ans: — Specialized macrophages that phagocytize dead
tissue and foreign substances
© 2025 All rights reserved
, 2 | Page
Oligodendrocytes Ans: — Form myelin sheath on axons in the CNS
Schwann cells Ans: — Form myelin sheath on axons in the PNS
Neuron Ans: — Transmits electrical signals
Dendrites Ans: — Receive signals coming into the neuron
Axon Ans: — Long projection that carries action potentials
Nerve Ans: — Bundle of many axons in the PNS
Tract Ans: — Bundle of many axons in the CNS
Nucleus Ans: — Bundle of neuron cell bodies in the CNS
Ganglion Ans: — Bundle of neuron cell bodies in the PNS
Myelin sheath Ans: — Insulates and electrically insulates axons
Node of Ranvier Ans: — Gap between myelin sheaths where action
potentials are generated
Multipolar neuron Ans: — Neuron with many dendrites and one
axon
Bipolar neuron Ans: — Neuron with one dendrite and one axon
Unipolar neuron Ans: — Neuron with one process that acts as both
the dendrite and axon
Voltage Ans: — Measure of the potential energy generated by
separation of different charges
Current Ans: — Flow of electrical charge between two points
Resistance Ans: — Hindrance to charge flow
Leakage channel Ans: — Always open, allows ions to diffuse down
electrochemical gradient
Ligand-gated channel Ans: — Opens with binding of a specific
chemical
Voltage-gated channel Ans: — Opens and closes in response to
changes in membrane potential
© 2025 All rights reserved
