Nervous System Flashcards
the integrative functions of the nervous system are performed mainly by
interneurons
neurons arise from embryonic
ectoderm
the soma of a mature neuron lacks
centrioles
the glial cells that destroy microorganisms in the CNS are
microglia
a friend takes a flash photograph of you, and you continue to see an image of the flash unit for several seconds afterward. This phenomenon is the result of a ___ circuit
parallel after discharge
neurotransmitters are found in
the presynaptic terminal
another name for the axon of a neuron is
nerve fiber
nerves that directly control the motility of the stomach or rate of the heartbeat would belong to
the visceral motor division
the glial cells that guide migrating neurons in the developing fetal brain are
astrocytes
which of the following appears earlier than all the rest in prenatal development of the nervous system
the neural plate
neurons that convey information to the CNS are called sensory, or ___, neurons
afferent
motor effects that depend on repetitive output from a neural pool are most likely to use the ___ type of neural circuit
reverberating
prenatal degeneration of the forebrain results in a birth defect called
anencephaly
neurons receive incoming signals by way of specialized processes called
dendrites
in the central nervous system, cells called ___ perform one of the same functions that Schwann cells do in the peripheral nervous system.
oligodendrocytes
a/ an ___ synapse is formed when a presynaptic neuron synapses with the cell body of postsynaptic neuron
axosomatic
all of the nervous system except the brain and spinal cord is called
peripheral nervous system
the ___ and ___ are necessary for regeneration of damaged nerve fibers in the peripheral nervous system
neurilemma, endoneurium
in the peripheral nervous system, the somas of the neurons are concentrated in enlarged, knotlike structures called ____ connected to the nerves
ganglia
at a given synapse, the ___ neuron has neurotransmitter receptors.
postsynaptic
below L2, the vertebral canal is occupied by a bundle of spinal nerve roots called
the cauda equina
the brachial plexus gives rise to all of the following nerves
axillary, radial, median, and ulnar
between the dura mater and vertebral bone, one is most likely to find
adipose tissue
which tract carries motor signals destined for the postural muscles
the vestibulospinal tract
a patient has a gunshot wound that caused a bone fragment to nick the spinal cord. The patient now feels no pain or temperature sensations from that level of the body down. Most likely, the ___ was damaged.
spinothalamic tract
what are the regions of the spinal cord
cervical, thoracic, lumbar, sacral
In the spinal cord, the Soma’s of the lower motor neurons are found in
The anterior horns
The outermost connective tissue wrapping of a nerve is called
The epineurium
The intercostal nerves between the ribs arise from which spinal nerve plexus
Thoracic
All somatic reflexes share all of the following properties
They are quick, they require stimulation, they are involuntary, they are stereotyped
Outside the CNS, the Somas of neurons are clustered in swellings called
ganglia
Distal to the intervertebral foramen, a spinal nerve branches into a posterior and anterior
rami
The cerebellum receives feedback from the muscles and joints by way of the ___ tracts of the spinal cord
spinocerebellar
Motor innervation of the leg proper comes predominantly from the ___ plexus
sacral
Neural circuits called ____ in the spinal cord produce the rhythmic muscular contractions of walking
central pattern generators
The ____ nerves arise from the cervical plexus and innervate the diaphragm
phrenic
The crossing of a nerve fiber or tract from the right side of the CNS to the left, or vice versa, is called
decussation
the nonvisual awareness of the body’s position and movements is called ___
proprioception
the ___ ganglion contains the somas of neurons that carry sensory signals to the spinal cord
posterior root
the sciatic nerve is a composite of two nerves, the ___ and ___
tibial, common fibular
what is caudal to the hypothalamus
the cerebral aqueduct
hearing is associated mainly with
the temporal lobe
the blood- CSF barrier is formed by
ependymal cells
the pyramids of the medulla oblongata contain
descending corticospinal fibers
what is involved in vision
the temporal lobe, the occipital lobe, the midbrain tectum, the trochlear nerve
while studying in a noisy cafeteria, you get sleepy and doze off for a few minutes. You awaken with a start and realize that all the cafeteria sounds have just “come back”. while you were dozing, this auditory input was blocked from reaching your auditory cortex by
the reticular activating system
because of a brain lesion, a certain patient never feels full, but eats so excessively that she now weighs nearly 600 pounds. the lesion is most likely in her
hypothalamus
the ___ is most closely associated with the cerebellum in embryonic development and remains its primary source of input fibers throughout life
pons
damage to the ___ nerve could result in defects of eye movement
abducens
all of the following, begin or end in the orbit
optic, oculomotor, trochlear, abducens
the right and left cerebral hemispheres are connected to each other by a thick C- shaped bundle of fibers called the
corpus callosum
the brain has four chambers called ___ filled with ___ fluid
ventricles, cerebrospinal
in a sagittal section, the cerebellar white matter exhibits a branching pattern called the
arbor vitae
part of the limbic system involved in forming new memories is the
hippocampus
cerebrospinal fluid is secreted partly by a mass of blood capillaries called the ___ in each ventricle
choroid plexus
the primary motor area of the cerebrum is the ___ gyrus of the frontal lobe
precentral
your personality is determined mainly by which lobe of the cerebrum
frontal
areas of cerebral cortex that identify or interpret sensory information are called
association cortex
linear, analytical, and verbal thinking occurs in the ___ hemisphere of the cerebrum, which is on the left in most people
categorical
the motor pattern for speech is generated in an area of cortex called the ___ and them transmitted to the primary motor cortex to be carried out
broca area
hot and cold stimuli are detected by
free nerve endings
sensory signals for all of the following, must pass through the thalamus before they can reach the cerebral cortex
taste, hearing, equilibrium, and vision
the vallate papillae are more sensitive to ___ than to any of these other tastes
bitter
the ear is somewhat protected from loud noises by
the stapedius
the sensory neurons that begin in the spiral organ of the ear end in
the cochlear nucleus
the spiral organ rests on
the basilar membrane
the acceleration you feel when an elevator begins to rise is sensed by
the macula sacculi
the highest density of cone cells is found in
the fovea centralis
the dilated blood vessels seen in “blood shot” eyes are vessels of
the conjunctiva
a person would look cross eyed if ___ muscles contracted at once
both medial rectus
the most finely detailed vision occurs when an image falls on a pit in the retina called
fovea centralis
fibers of the optic nerve come from the ___ cells of the retina
ganglion
a sensory nerve ending specialized to detect tissue injury and produce a sensation of pain is called a/ an
nociceptor
the gelatinous membranes of the macula sacculi and macula utriculi are weighted by calcium carbonate- protein granules called
otoliths
three rows of ___ in the cochlea have V- shaped arrays of stereocilia and tune the frequency sensitivity of the cochlea
outer hair cells
the ___ is a tiny bone that vibrates in the oval window and thereby transfers sound vibrations to the inner ear
stapes
the ___ of the midbrain receive auditory input and trigger the head- turning auditory reflex
inferior colliculi
the apical microvilli of a gustatory cell are called
taste hairs
olfactory neurons synapse with mitral cells and tufted cells in the ___, which lies inferior to the frontal lobe
olfactory bulb
in the phenomenon of ___, pain from the viscera is perceived as coming from an area of the skin
referred pain
