Seeley's Anatomy and Physiology chapter 11
Questions and Answers| Latest Update
Presynaptic terminals Small extensions with enlarged ends formed by axons that terminate
by branching
Sensory neurons Afferent neurons; conduct action potentials toward the CNS
Motor neurons Efferent neurons; conduct action potentials away from the CNS toward
muscles or glands
Interneurons Conduct action potentials from one neuron to another within the CNS
Gray matter Consists of groups of neuron cell bodies and their dendrites, where there is
very little myelin
Cortex Gray matter on the surface of the brain
Nuclei Clusters of gray matter located deeper within the brain
White matter Consists of bundles of parallel axons with their myelin sheaths
Potential difference The electrical charge difference across the plasma membrane
, Resting membrane potential The potential difference in an unstimulated, or resting, cell
Depolarization A decrease in the membrane potential caused by a decrease in the charge
difference across the plasma membrane
Hyperpolarization An increase in the charge difference across the plasma membrane.
Graded potential A change in the membrane potential that is localized to one area of the
plasma membrane
Action potential An electrical signal conducted from a neuron to its target; dependent on
graded potentials
Depolarization phase Phase in which the membrane potential moves away from the
resting state and becomes more positive
Repolarization phase Phase in which the membrane potential returns toward the resting
state and becomes more negative
Major functions of nervous system Receiving sensory input, integrating information,
controlling muscles and glands, maintaining homeostasis, establishing and maintaining mental
activity
Questions and Answers| Latest Update
Presynaptic terminals Small extensions with enlarged ends formed by axons that terminate
by branching
Sensory neurons Afferent neurons; conduct action potentials toward the CNS
Motor neurons Efferent neurons; conduct action potentials away from the CNS toward
muscles or glands
Interneurons Conduct action potentials from one neuron to another within the CNS
Gray matter Consists of groups of neuron cell bodies and their dendrites, where there is
very little myelin
Cortex Gray matter on the surface of the brain
Nuclei Clusters of gray matter located deeper within the brain
White matter Consists of bundles of parallel axons with their myelin sheaths
Potential difference The electrical charge difference across the plasma membrane
, Resting membrane potential The potential difference in an unstimulated, or resting, cell
Depolarization A decrease in the membrane potential caused by a decrease in the charge
difference across the plasma membrane
Hyperpolarization An increase in the charge difference across the plasma membrane.
Graded potential A change in the membrane potential that is localized to one area of the
plasma membrane
Action potential An electrical signal conducted from a neuron to its target; dependent on
graded potentials
Depolarization phase Phase in which the membrane potential moves away from the
resting state and becomes more positive
Repolarization phase Phase in which the membrane potential returns toward the resting
state and becomes more negative
Major functions of nervous system Receiving sensory input, integrating information,
controlling muscles and glands, maintaining homeostasis, establishing and maintaining mental
activity
