(Lesson 11) Central Nervous System Lab Flashcards
Central Nervous System
Composed of the brain and the spinal cord
Gray matter
surrounds the hollow central cavity of CNS. The site where neuron cell bodies are clustered (along with dendrites, short unmyelinated axons, and neuroglia)
H-Shaped region in the spinal cord. Dorsal half contains cell bodies of interneurons and ventral half contains cell bodies of motor neurons.
white matter
External to gray matter. Contains no cell bodies but composed of tracts of myelinated nerve fibers (millions of axons). White comes from myelin sheaths.
located beneath the cortex in brain and descend to spinal cord or vice versa to allow two CNS regions to communicate with each other.
Cerebrum
the large, main superior component of the brain in charge of memory and reason, is divided into hemispheres, and further into five lobes
cerebral gyrus
Twisted ridges and elevations of brain tissue on the cortical surface of the brain.
cerebral hemispheres
the right and left halves of the cerebrum
left hemisphere
memorizing, analytical and verbal skills
right hemisphere
pondering and solving
frontal lobe
comprises most of the anterior half of the cerebrum in charge of personality and contraction of skeletal muscle
parietal lobe
the top, posterior portion of the cerebrum, associated with speech, emotions, and visual interpretations
temporal lobe
the lateral portion of the cerebrum, associated with memory, hearing and visual activities
insula lobe
found deep beneath the lateral sulcus, function somewhat unknown
occipital lobe
most posterior portion of the cerebrum, associated with interpretation of usual images and eye movement
longitudinal fissure
deep groove that separates the right and left cerebral hemispheres, follows the sagittal sututre line
central sulcus
divides the brain in a coronal section, separates the frontal lobe from the parietal lobes
corpus callosum
a commissure connecting the two cerebral hemispheres, unifying awareness between them.
genu (corpus callosum)
anterior portion if the corpus callosum
splenium (corpus callosum)
posterior portion of the corpus callosum
thalamus
paired organ lateral and superior to third ventricle of the diencephalon, receives and sends impulses to precise locations within the cerebral lobes for interpretation. Every part of the brain that communicates with the cerebral cortex must relay it’s signal through the nucleus of the Thalamus.
interthalamic adhesion (intermediate mass)
a small, midline commissure connecting the right and left thalamus
hypothalamus
“master gland” located within the floor of the diencephalon or third ventricle
epithalamus
forms posterior root of diencephalon and covers third ventricle
infundibulum
the stalk that connects the pituitary gland to the hypothalamus
pituitary gland
a small endocrine gland projecting inferiorly from the hypothalamus and situated in the sella turcica of the sphenoid bone
mammillary body
two nodes located inferior to the third ventricle and superior and anterior to the pons, function a a relay center for olfactory sensations
pineal gland (body)
a small hormone secreting gland in the posterior portion of the epithalamus, third ventricle superior to the corpora quadrigemina of the mid brain. (pine cone shaped)
hippocampus
located in the medial temporal lobe underneath the cortical surface, has the shape of a curved tube, makes up part of the limbic system; plays a role in spatial navigation and long term memory
brain stem
consists of mid-brain, pons, and medulla oblongata
midbrain
consists of the cerebral peduncles anteriorly and the corpora quadrigemina posteriorly
cerebral peduncles
vertical pillars superior to the pons that form the ventral portion of the midbrain
corpora quadrigemina
four rounded elevations that form, in part, the dorsal portion of the midbrain
superior colliculus
larger than the inferior colliculus, responsible for visual reflexes. ie turning head when we see something out of the corner of our eye
inferior colliculus
responsible for auditory reflexes such as turning our heads towards a startling sound
pons
a mound inferior to the brain, caudal to the midbrain, contains respiratory centers. bridge
medulla oblongata
portion of the brainstem between the pons and spinal cord, regulates breathing, heart beat, and blood pressure
cerebellar peduncles
white matter tracts linking the cerebellum with the pons; the cerebellum receives motor movement information via this connection
cerebellum
relatively large posteriorly, inferior region of the brain involved in coordination and equilibrium. Little brain. Smooths and coordinates body movements that are directed by other brain regions and helps maintain posture and equilibrium.
cerebellar hemispheres
each half of the cerebllum
vermis
central area between the cerebellar hemispheres (worm)
arbor vitae
portion of the cerebellum composed of white matter, viewed in sagittal section. Tree of life.
Meninges
three distinct membranes that cover the brain and spinal cord for protection and for accommodation of blood vessels and cerebrospinal fluid. Membrane.

Dura Mater
outermost membrane in direct contact with the bones of the skull; which extends into the longitudinal fissure of the brain and attaches to the crista galli, is called falx cerebri. Tough mother
arachnoid matter
a net-like membrane located between the dura mater and the pia mater. spider-like.
pia mater
highly vascularized membrane which attaches directly to the brain and spinal cord and follows the contours, support the blood vessels that supply the brain and spinal cord, contributes to choroid plexus
Vertebral Arteries
Paired arteries originating from the subclavian arteries, passing through the foramen magnum, uniting to form the basilary artery
Basilar Arteries
central artery anterior to brain stem that branches to cerebellum, pons and inner ear
internal carotid arteries
paired arteries originating from the common carotid arteries, passing through the carotid canal of the temporal bone
Cerebral arterial circle of willis
series of vessels that encircle the pituitary gland, uniting anterior and posterior circulations
cerebrospinal fluid
CSF
A clear fluid found in the ventricles, central canal of the spinal cord, and subcranial space; serves as a protective cushion and source of nourishment to the brain
lateral ventricles
paired chambers located deep within each hemisphere below the corpus callosum

septum pellucidum
a vertical membranous wall just inferior to the body of the corpus callosum
third ventricle
narrow ventricle located in the diencephalon between the thalami
mesencephalic (cerebral) aqueduct
canal-like structure that connects the third ventricle to the fourth ventricle
fourth ventricle
located in the brain stem posterior to the pons and anterior to the cerebellum, connects with the central canal of the spinal cord
choroid plexus
a cluster of capillaries found lining the ventricles; produces cerebral spinal fluid

Anterior median fissure
a groove running the length of the spinal cord on the anterior aspect
posterior median sulcus
a groove running the length of spinal cord of the posterior aspect

gray matter
found on the inner potion of the spinal cord, is a muxture of unmyelinated association neurons , nerve cell bodies and neuroglia, forms the letter “H” in a cross section

white matter
outer portion of the spinal cord composed primarily of myelinated axons of sensory (ascending) and motor (descending) neurons
central canal
a canal that runs down the middle of the spinal column within the gray commissure and is filled with cerebral spinal fluid
anterior horns
the anterior arms of the inner portion of the spinal cord that contain cell bodies somatic motor cells and interneurons.
lateral horns
the lateral arms of the inner portion of the spinal cord that contain cell bodies of visceral motor cells and interneurons.
posterior horns
posterior arms of the inner portion of the spinal cord that contain cell bodies interneurons recieving input from somatic and visceral sensory neurons
anterior funiculi
the anterior columns of the white matter of the spinal cord containing fiber tracts
lateral funiculi
the lateral colums of the white matter of the spinal cord containing fiber tracts
posterior funiculi
the posterior columns of the white matter of the spinal cord containing fiber tracts
dorsal root ganglion
a bundle of sensory afferent nerve cell bodies
reflex arc
an automatic response by the nervous system to protect the body or to return a system to homeostasis (maintenance of constant conditions within the body)
Anatomy of reflec arc
receptor, sensory (afferent) neuron, association (inter) neuron, motor (efferent) neuron, and an effector
Receptor
(reflex arc)
the electrical impulse is initiated here and then sent to the cns, an example is the dendritic ending associated with the skin
sensory (afferent) neuron
(reflex arc)
conducts an impulse from a receptor organ such as the skin to the spinal cord
association (inter) neuron
(reflex arc)
associated with the center of the reflec arc, the actual sensory-motor arc is made here
motor (efferent) neuoron
(reflex arc)
conducts the impulse away from the cns to the effector organ such as a muscle or gland
effector
(reflex arc)
receives the impulse from the motor neuron and then responds, an example is a muscle