anatomy & physiology - functional organization of nervous tissue
Gaps or interruptions in the myelin sheath are called
nodes of Ranvier.
Clusters of gray matter deep within the brain are called
nuclei
The figure is a process figure of the chemical synapse. What does "E" represent?
postsynaptic membrane
A neuron that conducts pain sensations to the central nervous system would be classified as a(n)
sensory or afferent neuron.
The junction of a neuron with another cell is a/an
synapse
If the ECF around a nerve cell is replaced with an isotonic saline solution that contains potassium ions and other solutes at concentrations very close to the ECF concentrations of a normal cell, the result is
a resting membrane potential close to its normal value.
Voltage-gated sodium channels are sensitive to changes in the extracellular concentration of
calcium ions.
When two or more presynaptic neurons synapse with a single postsynaptic neuron in the CNS, a(n) _______ pathway is formed.
convergent
Sensory neurons carrying action potentials from pain receptors synapse within the spinal cord with interneurons. These interneurons synapse with motor neurons leading back to an effector and ascending neurons that carry action potentials toward the brain. This is an example of a(n) _____ pathway.
divergent
Gap junctions are functional __________ synapses.
electrical
Overproduction of cerebrospinal fluid could be the result of overactivity of the
ependymal cells.
Damage to a postsynaptic membrane would
interfere with the ability to respond to neurotransmitter.
The figure illustrates the Action Potential. What does "A" represent?
local potential
Saltatory conduction of an action potential means that
an action potential is conducted from one node of Ranvier to the next node.
Microglia
are phagocytic cells in the CNS.
Identify structure "C" on the neuron.
axon
A change in the resting membrane potential has the following characteristics (non-propagated, graded, can summate). This type of change can
be a local potential and a consequence of an increase in the permeability to Na+.
The strength of a stimulus is communicated through
both the frequency and the length of time action potentials are produced.
The blood-brain barrier
protects neurons from toxic substances in the blood.
Chemical synapses are characterized by
the release of neurotransmitter by the presynaptic terminal.