Lesson 9 Flashcards
neurons
nerve cells that function to transmit electrical impulses
neuroglia
cells that support the neurons
central nervous system
composed of the brain and spinal cord
peripheral nervous system
composed of the nerves that leave the CNS
astrocyte
most abundant CNS neuroglia
microglial cells
defensive cells in the CNS
ependymal cells
line cerebrospinal fluid-filled cavities
oligodendrocytes
have processes that form myelin sheaths around the CNS nerve fibers
satellite cells and Schwann cells
form myelin, surround neurons in the PNS
soma
the neuron’s cell body
axon hillock
tapered structure between the soma and axon, important for producing the action potential
dendrites
processes that conduct electrical impulses towards the soma, usually receives a signal from another cell
axon
process that conducts electrical impulses away from the soma
axon/synaptic terminal
found at the end of an axon
synaptic cleft
gap found between the axon of one neuron and the target cell
neuroplasma
cytoplasm
neurofibrils
cytoskeleton elements
nissl bodies
chromatophilic substance
- rough endoplasmic reticulum
neuroglia are important for neuron function because: (2)
- produce myelin to insulate axons
- form nodes of Ranvier, which help propagate and increase action potential
unipolar neuron
one very short process dividing into peripheral and central process from the soma
bipolar neuron
two processes attached to the soma
multipolar neuron
many dendrites and one axon attached to a soma
sensory/afferent neurons
neurons carrying impulses from sensory receptors to the CNS, usually unipolar, contains sensory fibers
motor/efferent neurons
neurons carrying impulses away from the CNS to muscles and glands, usually multipolar, contains motor fibers
interneurons
connects neurons in the sensory and motor pathways
mixed nerves
contains both sensory and motor fibers (spinal nerves)
endoneurium
surrounds each nerve fibers
perineurium
surrounds a group of nerve fibers to form fascicles
epineurium
surrounds a group of fascicles
somatic
voluntary muscle movements
autonomic
involuntary; subdivisons are the sympathetic and parasympathetic
forebrain
prosencephalon
- cerebrum, diencephalon
- thalamus, hypothalamus, and epithalamus
midbrain
mesencephalon
- midbrain, brain stem
hindbrain
rhombencephalon
- cerebellum, brain stem, and medulla oblongata
the prosencephalon splits into the _____ and _____
telencephalon, diencephalon
the rhombencephalon splits into the _____ and _____
metencephalon, myelencephalon
the telencephalon develops into the…..
cerebrum: cerebral hemispheres
the diencephalon develops into….. (4)
the thalamus, hypothalamus, and epithalamus
retina
the mesencephalon develops into…..
midbrain of the brain stem
the metencephalon develops into…. (2)
the pons of the brainstem and the cerebellum
the myelencephalon develops into…..
the medulla oblongata of the brainstem
the telencephalon has which neural canal region?
the lateral ventricles
the diencephalon has which neural canal region?
the third ventricle
the mesencephalon has which neural canal region?
cerebral aqueduct
the metencephalon and myelencephalon have which neural canal region?
the fourth ventricle
the spinal cord has which neural canal region?
the central canal
prefrontal cortex - function and location
frontal lobe; intelligence, complex reasoning, personality
primary motor cortex - function and location
precentral gyrus on the frontal lobe; responsible for conscious and voluntary movement
primary somatosensory cortex - function and location
postcentral gyrus of the parietal lobe; receives sensory information
somatosensory association cortex - function and location
posterior to primary somatosensory cortex; analyzes incoming stimuli for perception of a specific sensation
primary visual cortex - function and location
very back of the occipital lobe; responsible for vision
longitudinal fissure
separates the left and right hemispheres of the cerebrum
central sulcus
separates the frontal and parietal lobes
lateral sulcus
separates the parietal and temporal lobes
parieto-occipital sulcus
separates the parietal and occipital lobes
transverse cerebral fissure
separates the cerebrum from the cerebellum
Wernicke’s area - function and location
junction or parietal and temporal lobes; language perception
Broca’s area - function and location
base of prefrontal gyrus above the lateral sulcus; motor speech area
Uncus - function and location
on the medial surface of the temporal lobe; olfactory area
Wernicke and Broca’s areas are only in which hemisphere?
left, usually
diencephalon characteristics (4)
- olfactory bulbs and tracts
- optic nerves, chiasma, and tracts
- pituitary gland
- mammillary bodies
epithalamus structures (2)
- pineal body
- choroid plexus
pineal body
neuroendocrine structure involved in biological rhythm (day/night) cycle
thalamus
integration/relay sensory info to sensory cortex
Damage to what area can cause a person to go into a vegetative state?
thalamus
vegetative state
clinical loss of cerebral cortex function, person can display wakefulness without awareness
hypothalamus
regulates body temp, water balance, metabolism, etc.
the top of the diencephalon is marked by the _____ _____
corpus callosum
brain stem
connects cerebrum with lower CNS centers
- pons and medulla oblongata
pons
motor and sensory tracts connecting the brain with the lower CNS centers
medulla oblongata (3)
- contains motor tracts from the cerebellum descending down the spinal cord
- site of autonomic center that regulate heart rate, respiratory rhythm, blood pressure
- involuntary centers for swallowing and vomiting
cerebellum
muscle coordination, balance, and equilibrium
arbor vitae
white matter found in the cerebellum
what happens when CSF is not drained as fast as it is produced?
the increased CSF compresses neural tissue and causes damage in adults
hydrocephalus
when CSF doesn’t drain as fast as it is produced in infants; skull has fontanelles so it can expand to accomodate
I. Olfactory
smell/sensory
II. Optic
vision/sensory
III. Oculomotor
eye movement, iris contraction, vision focus/motor
IV. Trochlear
eye movement/motor
V. Trigeminal
chewing, facial sensations/both
VI. Abducens
eye movement/motor
VII. Facial
facial expressions, taste/both
VIII. Vestibulocochlear
hearing, equilibrium/sensory
IX. Glossopharyngeal
speech, swallowing, taste/both
X. Vagus
thoracic and abdominal viscera sensation; movement, speech, swallowing/both
XI. Accessory
head/shoulder movement/both
XII. Hypoglossal
tongue movement/motor