nervous system: BBB and cerebrum Flashcards
what is the blood brain barier?
special capillaries in brain form selective barriers; have
tight junctions between ependymal and capillary
thickened basal lamina
astrocytes wrap around capillaries
stimulate formation of tight junctions
make brain capillaries much less permeable
what substances can cross the BBB?
hydrophobic molecules (lipids) and gases
what does BBB regulate and restrict?
movement of all other molecules
what are the four main regions of the brain?
- cerebrum
- diencephalon
- brain stem
- cerebellum
characteristics of the cerebrum?
largest component (85% brain mass)
complex thought processing/memory
2 hemispheres(separated by longitudinal fissure)-joined by nerve tract (corpus callosum)
surface has gyri(folds) and sulci(grooves)
what are the four functional lobes
frontal, parietal, occipital, and temporal
what are the three regions of cerebrum?
cerebral cortex, white mater, and basal nuclei
function of the cerebral cortex?
motor-voluntary muscle control learned movements
sensory-interprets sensory stimuli(sound/vision/odors)
association-integration of sensory info (memory)
characteristics of cerebral cortex?
most superficial
grey matter(cell bods of neurons/neurgolia)
has gyri and sulci
home of consciousness
functions of the white matter?
myelinated axons communicate with other parts of the brain
axons bundled into nerve tracts
three types of fibres in white matter?
commisural fibres- connect L/R cerebral hemi ex corpus callosum
association fibres- connections within the same hemi ex fornix
projection fibres- connect cerebral cortex with deeper parts of the brain ex tracts
characteristics of basal nuclei?
paired masses of grey matter (inferior to lateral ventricles)
caudate nuclei and lentiform nucleus (intiate/regulate voluntary movement)
claustrum(subconscious processing of visual stimuli )
functions of frontal lobe?
primary motor cortex
voluntary control of skeletal muscles
decision making and impulse control
primary motor cortex in the protectional gyrus
functions of parietal lobes?
primary sensory cortex
conscious perception of touch pain temp taste
primary sensory cortex in the parietal gyrus
function of occipital lobes
visual cortex
conscious perception of visual stimuli