Exam 3 Part 1 Flashcards
Brain
part of CNS; encased by cranium, meninges, and cerebrospinal fluid
2% of body weight, used 20% of blood O2
Main parts of brain
cerebrum, diencephalon, brain stem, cerebellum
parts of notochord that make up brain
prosencephalon
mesencephalon
rhombencephalon
Prosencephalon
top of notochord, makes up forebrain (cerebrum and diencephalon)
Mesencephalon
middle of notochord, develops into midbrain
Rhombencephalon
bottom of notochord, develops into hindbrain (pons, cerebellum, medulla oblongata)
brainstem
pons and medulla oblongata
NOT rhombencephalon
surface of brain
foldings increase area/intelligence/thinking
not present in embryo
Ridges of brain
gyri
Grooves of brain
sulci (fissure if deep)
Distinct fissures
Transverse fissure, lateral sulcus, central sulcus
Layers of brain
made up of gray and white matter- follow convolution of surface
gray matter
nerve cell bodies; UNmyelinated axons
outerareas (cerebral cortex, cerebellar cortex)
Seen as collections of nerve cell bodies deep within white matter (cerebral nuclei/basal nuclei)
bellum
little
cortex
bark
white matter
deeper areas of brain; myelinated axons
fibers form bundles called tracts or commissures; transmit information
–corpus callosum
–septum pellucidum
Cerebrum
largest part of brain -80% brain mass
2 hemispheres
separated form cerebellum by tranverse fissure
each hemisphere have 5 lobes
cerebrum hemispheres
partly separated by longitudinal fissue
connected internally by corpus callosum
each has cavity -lateral ventricles, contains CSF
Cerebral lobes
frontal parietal temporal occipital insula
frontal lobe
central sulcus to lateral sulcus
precentral gyrus -contains primary motor cortex; many pyramidal cells
Motor speech area (broca’s area)
primary motor cortex
found in precentral gyrus of frontal lobe
voluntary muscle control, higher intellectual functinos, personality
Parietal lobe
part of cerebrum.
post central gyrus
Wernicke’s area
Post central gyrus
found in parietal lobe
primary somatosensory area (touch, pressure, pain, temp receptors)
Wernike’s Area
found in parietal lob (also temporal)
usually in left hemisphere
mental aspects of speech/language