Chapter 11 A+P I
Terms in this set (55)
Bundles of axons in the PNS
Nerves
Clusters of cell bodies in the PNS
Ganglia
Bundles of axons in the CNS
Tracts
Clusters of cell bodies in the CNS
Nuclei
Regulation of heart rate, blood pressure, and digestive functions are carried out by the ______________________.
Autonomic Nervous System
Which neuroglial cells help form the blood-brain barrier?
Astrocytes
What specific part of the neuron communicates with a target cell and serves as the secretory region of the cell?
Axon terminals (synaptic knobs)
What cell type forms the myelin sheath in the central nervous system (CNS)?
Oligodendrocytes
What is the ciliated neuroglial cell that functions to circulate cerebrospinal fluid?
Ependymal Cells
The majority of neurons are functionally classified as _________ neurons.
Interneurons
Which of the following are organs of the central nervous system?
Brain and Spinal Cord
What forms the white matter of the spinal cord?
Myelinated Axons
Releases neurotransmitters to communicate with other neurons
Axon Terminals
Integrates incoming signals and generates outgoing signal to axon
Axon Hillock
Conducts electrical impulses away from the neuron's cell body
Axon
Receives electrical signals from other neurons
Dendrites
Maintains the cell's life functions and contains the nucleus
Soma (cell body)
The most common type of neuron in the human body is __________.
Multipolar
The conducting region of the neuron is the __________.
Axon
Which division of the peripheral nervous system (PNS) carries signals from bones, joints, skin, and organs of vision to the central nervous system (CNS)?
Somatic Sensory
Bundles of axons known as tracts are part of the __________.
Central Nervous System (CNS)
Most sensory neurons such as the ones found in the special sense organs are structurally classified as ____________ neurons.
Bipolar
Neurons that carry signals from the central nervous system
Motor (efferent)
Controls voluntary movements
Somatic
Related to the internal organs of the body
Visceral
Neurons that transmit signals to the central nervous system
Sensory (afferent)
Neurons that process information within the central nervous system
Interneuron
Which of the following effectors is controlled by the somatic motor division?
Skeletal Muscle
The autonomic nervous system does not carry signals to __________.
Skeletal Muscle
A series of measurements with a voltmeter show a neuron's membrane potential becoming more negative, from –70 mV to –85 mV. This neuron is experiencing a __________.
Hyperpolarization Phase
Which type of fiber has the slowest conduction speed?
Type C
Which type of fiber has the largest diameter?
Type A
The influx of positive charges makes the membrane potential more positive and is known as __________.
Depolarization
Which of the following events is most likely to trigger an action potential?
Excitatory postsynaptic potential (EPSP)
Which of the following events occurs when EPSPs arrive rapidly at a single synapse?
Temporal Summation
What kind of conduction occurs when each section of the axolemma has to be depolarized to threshold in sequence along the entire axolemma for a current to spread down the length of the axon?
Continuous
What is the resting membrane potential of a typical neuron?
-70 mV
Which of the following terms refers to the neuron that delivers a message to a target cell?
Presynaptic
What ion triggers synaptic vesicles to release neurotransmitters into the synaptic cleft?
Calcium
Influx of which of the following ions can cause an inhibitory postsynaptic potential (IPSP) to be produced?
Chloride Ions
During saltatory conduction, action potentials are generated __________.
Only at nodes of Ranvier of myelinated axons
What is the period during an action potential when a nerve fiber cannot be stimulated to produce an additional action potential no matter how strong the stimulus?
Absolute Refractory Period
What term refers to a temporary change in the cell’s membrane potential that makes it less negative (or more positive)?
Depolarization
What is thought to be one of the major neurotransmitters involved in mood regulation, motor behaviors, feeding behaviors, and daily rhythms and is a common target in the treatment of depression?
Serotonin
Which neurotransmitter is the most important inhibitory neurotransmitter in the brain?
GABA
What type of neurotransmitter receptors elicit much slower changes in the membrane potential of the postsynaptic neuron, but the effects are typically longer lasting and more varied?
metabotropic receptors
Which neuropeptide neurotransmitter is released from fibers transmitting sensory information about pain and temperature?
Substance P
Cholinergic synapses use the neurotransmitter __________.
Acetylcholine
Which of the following pairs of neurotransmitters are strictly inhibitory?
Glycine and Gaba
Which neurotransmitter is widely used by the autonomic nervous system (ANS), where it influences functions such as heart rate, blood pressure, and digestion?
Norepinephrine
What change in membrane potential is caused when glycine and GABA stimulate the opening of chloride ion channels?
Hyperpolarization
How many neurotransmitters operating in the human nervous system have been identified?
More than 100
What is considered to be the most important excitatory neurotransmitter in the brain?
Glutamate
What are the main types of neurotransmitter receptors?
Ionotropic and Metabotropic
The same __________ can have different effects depending on the properties of the __________.
Neurotransmitter; Receptor