Shared Flashcard Set

Details

Chapter 6
Parts of the Nervous System
119
Other
Undergraduate 3
09/10/2015

Additional Other Flashcards

 


 

Cards

Term
Where does the spinal cord lay?
Definition
in the vertebral canal
Term
Where is the brain located?
Definition
in the cranial cavity
Term
brain stem
Definition
the upward rostral continuation of the spinal cord into the brain (but has a more complex internal organization)
Term
What 2 structures largely cover the brain stem & constitute the major part of the brain?
Definition
cerebellum & cerebrum (cerebral hemispheres)
Term
Where is the gray matter located in the spinal cord relative to the white matter?
Definition
central region of gray matter surrounded by white matter
Term
2 subdivisions of gray matter neurons in the spinal cord
Definition
1. motor neurons
2. sensory neurons
Term
Where do motor neurons in the spinal cord send their axons?
Definition
out of the cord to reach muscles & glands
Term
Where do sensory neurons in the spinal cord send their axons?
Definition
to the brain to transmit information received from the sense organs of the body
Term
spinal interneurons & propriospinal neurons
Definition
ensure communication among neurons in the spinal cord
Term
What is in the white matter of the spinal cord?
Definition
ascending tracts carrying signals to higher levels & descending tracts enabling the brain to control spinal cord neurons
Term
Is the spinal cord segmented?
Definition
yes!
Term
What do spinal cord segments give rise to?
Definition
pairs of spinal nerves
Term
nerve root
Definition
how each spinal nerve connects with the cord; there is a dorsal & a ventral
Term
dorsal roots
Definition
carry only sensory nerve fibers
Term
spinal ganglion
Definition
the cell bodies of sensory neurons of each dorsal root; appears as an ovoid enlargement of the dorsal root
Term
4 parts of the brain stem
Definition
1. medulla oblongata
2. pons
3. mesencephalon
4. diencephalon
Term
How many cranial nerves emanate from the brain stem?
Definition
12
Term
olfactory nerve
Definition
the first cranial nerve; serves the sense of smell
Term
optic nerve
Definition
the second cranial nerve; transmits signals from the retina
Term
oculomotor, trochlear, & abducens nerves
Definition
the third, fourth, & sixth cranial nerves; control the movements of the eye ball
Term
trigeminal nerve
Definition
the fifth cranial nerve; emanates from the pons & brings sensory signals from the face as well as motor signals to the masticatory muscles
Term
facial nerve
Definition
the seventh cranial nerve; innervates the mimic muscles of the face
Term
vestibulocochlear nerve
Definition
the eighth cranial nerve; carries signals from the vestibular apparatus & the cochlea
Term
glossopharyngeal nerve
Definition
the ninth cranial nerve; concerned mainly with sensation & movements of the pharynx, including taste impulses from the back of the tongue
Term
vagus nerve
Definition
the tenth cranial nerve; participates in the innervation of the pharynx & in addition innervates the larynx & sends motor signals to the heart, the lungs, & most of the gastrointestinal tract
Term
accessory nerve
Definition
the eleventh cranial nerve; innervates two muscles in the neck
Term
hypoglossal nerve
Definition
the twelfth cranial nerve; the motor nerve of the tongue
Term
cranial nerve nuclei
Definition
where the cranial nerves arise (both sensory & motor)
Term
reticular formation
Definition
diffuse collections of neurons in between the cranial nerve nuclei
Term
5 functions of the reticular formation
Definition
1. circulation
2. respiration
3. sleep
4. wakefulness
5. eye movements
Term
2 things that make up the bulk of the diencephalon
Definition
1. thalamus
2. hypothalamus
Term
How can you visually identify the thalamus?
Definition
it is a large, egg-shaped collection of nuclei in the center of the cerebral hemispheres
Term
hypothalamus
Definition
concerned mainly with the control of autonomic & endocrine functions that serve to maintain bodily homeostasis
Term
cerebral cortex
Definition
a folded sheet of gray matter covering the cerebral hemispheres
Term
distributed networks
Definition
interconnect neurons in many areas of the cerebral cortex that work together to perform specialized tasks
Term
pyramidal tract
Definition
a descending tract from the cerebral cortex that targets motor neurons in the spinal cord & brain stem
Term
corpus callosum
Definition
consists of commissural fibers & enables cooperation between the two cerebral hemispheres & cognitive functions
Term
basal ganglia
Definition
several large nuclei in the interior of the cerebral hemispheres; contributes to the control of movements
Term
striatum
Definition
the putamen & caudate nucleus; receives its main afferents from the cerebral cortex
Term
2 places that the striatum sends its efferents
Definition
1. globus pallidus
2. substantia nigra
Term
cerebellum
Definition
situated dorsal to the brain stem in the posterior cranial fossa; consists of a thin sheet of highly folded gray matter & a group of centrally located deep cerebellar nuclei; plays a decisive role in coordination of voluntary movements by acting on motor neurons in the cerebral cortex, brain stem, & spinal cord
Term
2 parts of the cerebellum
Definition
1. vermis (narrow middle part)
2. hemispheres (the more bulky lateral parts)
Term
2 lobes of the cerebellum
Definition
1. anterior lobe
2. posterior lobe
Term
medullary conus
Definition
a wedge-shaped end at the upper margin of the second lumbar vertebra in the spinal cord
Term
Does thickness of the spinal cord increase or decrease caudally?
Definition
decreases (except for the cervical & lumbar enlargements)
Term
anterior (ventral) median fissure
Definition
a longitudinal furrow (fissure) in the midline along the anterior aspect of the cord
Term
posterior (dorsal) median fissure
Definition
a corresponding, but shallower, furrow in the midline compared to the anterior median fissure that is at the posterior aspect of the cord
Term
anterior & posterior lateral sulci
Definition
shallow, longitudinal sulci located anteriorly & posteriorly on each side of the spinal cord
Term
Why is the color of the spinal cord whitish?
Definition
the outer part consists of axons, many of which are myelinated
Term
What is the consistency of the spinal cord like?
Definition
soft & jellylike (like the rest of the CNS)
Term
peripheral nerves
Definition
axons mediating communication between the CNS & other parts of the body
Term
rootlets
Definition
small bundles in which axons of the peripheral nerves leave & enter the spinal cord
Term
nerve root
Definition
a thicker strand of several adjacent rootlets
Term
intervertebral foramen
Definition
where the spinal ganglion lies; located where the dorsal & ventral roots unite
Term
How many pairs of thoracic nerves do we have?
Definition
12
Term
How many pairs of lumbar nerves do we have?
Definition
5
Term
How many pairs of sacral nerves do we have?
Definition
5
Term
How many pairs of cervical nerves do we have?
Definition
8
Term
cauda equina
Definition
the collection of dorsal & ventral roots that run longitudinally below the conus in the vertebral canal
Term
How is the white matter of the spinal cord divided?
Definition
into funicles (columns) by drawing lines in the transverse plane from the sluci on the surface of the cord to the center
Term
3 divisions of white matter in each half of the spinal cord
Definition
1. a ventral (anterior) funicle
2. a lateral funicle
3. a dorsal (posterior) funicle (AKA dorsal column)
Term
3 main types of gray matter neurons in the spinal cord
Definition
1. neurons sending their axons out of the CNS
2. neurons sending their axons to higher levels of the CNS
3. neurons sending their axons to other parts of the spinal cord
Term
somatic motor neurons (motoneurons)
Definition
large, multipolar cell bodies that are located in the ventral horn proper of the spinal cord
Term
autonomic motor neurons
Definition
a group of neurons that send their axons out of the spinal cord through the ventral root to supply smooth muscles & glands with motor signals
Term
preganglionic
Definition
neurons that send their axons to a ganglion
Term
intermediolateral cell column
Definition
formed by the autonomic motor neurons in the thoracic & upper two lumbar segments of the spinal cord & belongs to the sympathetic part of the autonomic nervous system
Term
sensory (afferent) nerve fibers (AKA spinal ganglion cells)
Definition
conduct impulses from the receptors & enter the spinal cord through the dorsal roots & ramify to form the terminals in the gray matter of the spinal cord
Term
spinal ganglia
Definition
where sensory neurons have their cell bodies in the spinal cord
Term
laminae
Definition
the columns in the ventral horn & the slabs in the dorsal horn of the spinal cord
Term
Where are laminae I-VI located?
Definition
the dorsal horn
Term
Where is lamina IX located?
Definition
columns of motoneurons in the ventral horn
Term
lamina II (substantia gelatinosa)
Definition
control of signals from pain receptors; control how much a painful stimulus hurts
Term
Where is lamina VII located?
Definition
the transition between the dorsal & ventral horns & contains mostly interneurons
Term
Where is lamina VII located?
Definition
medially in the ventral horn; contains many neurons that send axons to the other side of the spinal cord
Term
branches (rami)
Definition
divisions of each spinal nerve just outside the intervertebral foramen
Term
What is the thickest rami?
Definition
the ventral ramus
Term
What is the thinner branch of rami?
Definition
the dorsal ramus
Term
plexuses
Definition
formed from the joining of some ventral rami to each other
Term
meningeal ramus
Definition
a small branch sent off by each spinal nerve to pass back through the intervertebral foramen to reenter the vertebral canal
Term
2 dilated parts of the cavity in the brain stem
Definition
1. the fourth ventricle (at the level of the medulla & the pons)
2. third ventricle (situated in the diencephalon)
Term
pyramidal decussation
Definition
bundles of fibers that cross the midline close to the lower end of the medulla on the transition to the spinal cord
Term
inferior olivary nucleus
Definition
a large nucleus that forms the oval protrusion lateral to the pyramid; sends its efferents to the cerebellum
Term
What are the 2 longitudinal protrusions at caudal levels on the dorsal side of the medulla oblongata?
Definition
the gracile & cuneate tubercles
Term
Where is the rhomboid fossa located?
Definition
rostral to the upper end of the dorsal column nuclei; flattened, diamond-shaped; extends rostrally onto the posterior face of the pons
Term
What can be found on the dorsal side of the mesencephalon?
Definition
4 small, rounded protrusions (2 on each side of the midline)
Term
2 things that make up the colliculi
Definition
superior colliculus & inferior colliculus
Term
aqueduct
Definition
a narrow canal that interconnects the third & fourth ventricles; can be seen along the midline just ventral to the colliculi; looks like a small hole
Term
periaqueductal gray
Definition
a region of gray matter that surrounds the aqueduct & coordinates behavioral responses to stressful events & influences pain perception
Term
internal medullary lamina
Definition
narrow bands of white matter that form a Y to subdivide the thalamus in the frontal section of the brain
Term
3 main parts of the thalamic gray matter
Definition
1. anterior nuclear group
2. medial nuclear group
3. lateral part/region made up of a dorsal & a ventral nuclear group
Term
pulvinar
Definition
continuous with the lateral part of the thalamus; makes up most of the posterior part of the thalamus
Term
2 nuclei partly covered by the pulvinar that are included in the posterior part of the thalamus
Definition
lateral geniculate body & medial geniculate body
Term
optic chiasm
Definition
where the optic nerves from the two eyes unite just underneath the diencephalon; there is a partial crossing of the optic nerve fibers here
Term
hypothalamic sulcus
Definition
a shallow sulcus that marks the border between the thalamus & the hypothalamus
Term
mammillothalamic tract
Definition
a distinct fiber bundle formed from the major efferent pathway of the mammillary body to the thalamus
Term
tuber cinereum
Definition
the region between the mammillary bodies & the infundibulum
Term
2 parts of the pituitary
Definition
1. posterior lobe (developed from the CNS)
2. anterior lobe (developed from the epithelium in the roof of the mouth)
Term
Does each of the cerebral hemispheres contain a lateral ventricle?
Definition
yes!
Term
interventricular foramen
Definition
a small opening through which the lateral ventricles are continuous with the third ventricle
Term
association fibers
Definition
fibers interconnecting neurons in various parts of the cerebral cortex of one hemisphere
Term
insula
Definition
the small gyri in the bottom of the lateral sulcus
Term
central sulcus
Definition
separates the frontal lobe from the parietal lobe & extends from the medial edge of the hemisphere laterally to the lateral sulcus
Term
motor cortex (MI)
Definition
is of special significance for the execution of voluntary movement
Term
postcentral gyrus
Definition
major receiving region for sensory impulses from the skin, the musculoskeletal system, & the viscera; located just posterior to the central sulcus
Term
visual cortex
Definition
the main cortical region receiving information from the eyes; located in the occipital lobe around a deep sulcus (the calcarine sulcus)
Term
auditory cortex
Definition
the cortical region receiving impulses from the cochlea in the inner ear; located in the superior temporal gyrus of the temporal lobe
Term
How does the olfactory cortex receive fibers?
Definition
from the olfactory bulb through the olfactory tract
Term
The hippocampus & adjoining cortical regions in the medial part of the temporal lobe are of particular interest with regard to _____ & _____
Definition
learning & memory
Term
What is in layer 1 of the cerebral cortex?
Definition
cell poor & consists largely of dendrites from neurons with cell bodies in deeper layers & of axons with terminals making synapses on the dendrites
Term
What is in layers 2 & 4 (AKA external & internal granular layer) of the cerebral cortex?
Definition
small, rounded cells
Term
What is in layers 3 & 5 of the cerebral cortex?
Definition
cells that are larger than those in layers 2 & 4 are & cell bodies that tend to be pyramidal in shape (pyramidal cells)
Term
What is in layer 6 of the cerebral cortex?
Definition
cell bodies that are smaller & more spindle-shaped than those in layer 5 are
Term
What is the role of the interneurons in the cerebral cortex?
Definition
to provide opportunity for cooperation between the various layers & between neurons in different parts of one layer
Term
How many cortical areas exist in the cerebral cortex of each hemisphere?
Definition
about 50
Term
What is the largest part of the basal ganglia?
Definition
lentiform nucleus
Term
2 parts of the caudate nucleus
Definition
1. caput (an anterior bulky part)
2. cauda (a progressively thinner part)
Term
claustrum
Definition
a sheet of gray matter lateral to the putamen
Term
inferior cerebellar peduncle (AKA restiform body)
Definition
contains fibers that carry impulses from the spinal cord to the cerebellum
Term
superior cerebellar peduncle (AKA brachium pontis)
Definition
conveys information from the cerebral cortex
Supporting users have an ad free experience!