Ch 7 The Structure of the Nervous System Flashcards
anterior / rostral
“beak”; direction pointing to the nose
posterior / caudal
“tail”; direction toward the tail
dorsal
“back”; the direction pointing up
ventral
“belly”; the direction pointing down
midline
the invisible line running down the middle of the nervous system
medial
structures closer to the midline
lateral
structures away from the midline
ipsilateral
structures on the same side
contralateral
structures on the opposite sides
midsagittal plane
splitting the brain into equal left and right halves
sagittal plane
sections parallel to the midsagittal plane
horizontal plane
parallel to the ground
coronal plane
perpendicular to the ground and the sagittal plane
central nervous system CNS
consists of the parts of the nervous system encased in bone (the brain and the spinal cord)
cerebrum
rostral-most and largest part of the brain
left hemisphere controls right body
cerebral hemispheres
cerebrum split into equal sides by the sagittal fissure.
left hemisphere controls right body
cerebellum
lies behind the cerebrum
contains as many neurons as cerebrum
movement control center
left side controls left body
brain stem
forms the stalk from which the cerebral hemispheres and the cerebellum spout.
relays info from the cerebrum to the spinal cord and cerebellum & back
regulates vital functions
spinal cord
encased in the bony vertebral column and is attached to the brain stem
major conduit of info from the skin, joints, and muscles of the body to the brain & back
spinal nerves
way the spinal cord communicates with the body
part of the PNS
exit the spinal cord through notches between vertebra
dorsal root
contains axons that brings info into the spinal cord
ventral root
contains axons that carry info away from the spinal cord
Peripheral Nervous System PNS
all parts of the nervous system other than the brain and spinal cord
2 parts: Somatic and Visceral
Somatic PNS
all the spinal nerves that innervate the skin, the joints, and the muscles that are under voluntary control
Dorsal Root Ganglia
clusters outside the spinal cord that are made up of cell bodies of the somatic sensory neurons
each spinal nerve has a dorsal root ganglia
Visceral PNS
involuntary, vegetative, autonomic nervous system (ANS), consists of the neurons that innervate the internal organs, blood vessels, and glands
Visceral sensory axons brings info about visceral function to the CNS
afferent
carry to
efferent
carry from
cranial nerves
12 pairs of nerves that arise from the brain stem and innervate the head
meninges
3 membranes that protects the CNS : dura mater, the arachnoid membrane, and the pia mater
dura mater
outermost meninge
forms a tough, inelastic bag that surrounds the brain and spinal cord
contains blood vessels
arachnoid membrane
under the dura mater;
has an appearance and consistency resembling a spider web
blood collects here if vessels are ruptured from the dura mater
pia mater
thin membrane that adheres closely to the surface of the brain
along the pia run many blood vessels that ultimately dive into the substance that of the underlying brain
cerebrospinal fluid CSF
salty clear liquid that allows the brain to float inside the head
ventricular system
fluid-filled caverns and canals inside the brain
contains the choroid plexus that produces CSF
neural tube
formed by the neural folds that move together and fuse dorsally
The entire CNS develops from the walls of the neural tube
neural crest
neural ectoderm is pinched off from the neural folds and lies just lateral to the neural tube
All neurons with cell bodies in the PNS derive from the neural crest
neurulation
the process by which the neural plate becomes the neural tube
differentiation
the process by which structures become more complex and functionally specialized during development
forebrain
prosencephalon; rostral-most vesicle
midbrain
behind the prosencephalon lies another vesicle called the mesencephalon
hindbrain
caudal to the third primary vesicle is the rhombencephalon
connects with the caudal neural tube, which gives rise to the spinal cord
diencephalon
the unpaired structure that remains after the secondary vesicles have sprouted off
“between brain”
telencephalon
“end brain”
formed by the telencephalic vesicles
consists of the cerebral hemispheres
olfactory bulbs
participates in the sense of smell
formed by pair of vesicles sprouting off the ventral surfaces of the cerebral hemispheres
lateral ventricles
fluid-filled spaces within the cerebral hemispheres
third ventricle
space at the center of the diencephalon
cerebral cortex
formed by 2 different types of gray matter in the telencephalon
basal telencephalon
formed by 2 different types of gray matter in the telencephalon
thalamus
diencephalon differentiates into
hypothalmus
diencephalon differentiates into
cortical white matter
contains all the axons that run to and from the neurons in the cerebral cortex
corpus callosum
continuous with with the cortical white matter and forms an axonal bridge that links cortical neurons of the 2 cerebral hemispheres
internal capsule
continuous with the cortical white matter; links the cortex with the brain stem, particularly the thalmus
tectum
dorsal surface of the mesencephalic vesicle
tegmentum
the floor of the midbrain
cerebral aqueduct
CSF-filled space between constricts into a narrow channel; connects rostrally with the third ventricle of the diencephalon
pons
develop from the rostral half of the hindbrain (mytencephalon)
medulla oblongata
develops from the caudal half (myelencephalon)
fourth ventricle
continuous with the cerebral aqueduct of the mindbrain
spinal cord
transformation of the caudal neural tube
dorsal horn
upper part of the butterfly’s wing; contains gray matter (where neurons are)
ventral horn
lower part of the butterfly;s wing; contains gray matter (where neurons are)
sulci
the grooves in the surface of the cerebrum
gyri
the bumps of the cerebrum
temporal lobe
the tip of the “horn” lies right under the temporal bone
frontal lobe
portion of the cerebrum lying just under the frontal bone of the forehead
central sulcus
marks the posterior border of the frontal lobe
parietal lobe
portion of the brain caudal to the central sulcus, under the parietal bone
occipital lobe
at the back of the cerebrum, under the occipital bone
hippocampus
medial to the lateral ventricle is a piece of cortex that is folded onto itself in a peculiar shape
olfactory cortex
connected to the hippocampus ventrally and laterally, has 2 cell layers; continuous with the olfactory bulb; separated by a sulcus called the rhinal fissure
neocortex
neocortex is only found in mammals;
cytoarchitectural map
each area of the cortex having a common cytoarchitecture is given a number. Korbinian Brodmann founded it
