Brain-Anatomy Final

brain stem
the portion of the brain, consisting of the medulla oblongata, pons Varolii, and midbrain, that connects the spinal cord to the forebrain and cerebrum
the largest part of the brain and is the center of learning, volutary movement and the interpretation of sensation
part of the brain below the back of the cerebrum. it regulates balance, posture, movement, and muscle coordination.
cranial nerves
any of several nerves that arise in pairs from the brainstem and reach the periphery through openings in the skull...12 in humans and mammals
corpus callosum
a large bundle of nerve fibers that connect the left and right cerebral hemispheres
dura mater
tough fibrous membrane covering the brain and spinal cord and lining the inner surface of the skull
frontal lobe
one of the four lobes of the brain...largest and most anterior
outward fold on the surface of the cerebral cortex; ridge on surface of cerebrum
the part of the brain that lies below the thalamus functining to regulate bodily temp., certain metabloic processes, and other autonomic activities.; part of diencephalon that forms lower walls and floor of third ventricle
medulla oblongata
the lowermost portion of the vertebrate brain, continuous with the spinal cord, responsible for the control of respiration, circulation, and certain other bodily functions
the middle portion of the brain; part of brainstem between diencephalon and pons
occipital lobe
one of the four lobes of the brain...posterior lobe of each cerebral hemisphere
parietal lobe
one of the four lobes of the brain...middle portion of each cerebral hemisphere
a band of nerve fibers linking the medulla oblongata and the cerebellum with the midbrain; rounded bulge on underside of brainstem
Compare the relative sizes of the sheep and human cerebral hemispheres.
The cerebral hemisphere of a human is larger than a sheep.
compare the gyri and sulci in a sheep and human brain.
the human brain has more contours than a sheep's brain b/c the human brain has a larger surface area.
a groove or depression on the surface of the brain seperating the gyri
temporal lobe
one of the four lobes of the brain...contain sensory center of hearing.
why is a human brain bigger than a sheep brain and the gyri and sulci in them?
since the human brain is larger than the sheep brain, humans have more motor control and learning abilities. although sheep have smaller and less developed cerebrums, they have more acute senses b/c they have larger olfactory bulbs.
what structural differences are there between sheep and human cerebellum?
the sheep cerebellum was much smaller than the human cerebellum. the human brain is rounder while the sheep brain was longer. there were arlso more convolutions and sulci on the human brain which allows an increase of surface area
how does size of the sheep olfactory bulbs comapre to those of the human?
the olfactory bulb is larger in a sheep brain than in the human brain. this larger olfactory bulb allows the sheep to have a stronger sense of smell which is vital to its survival.
based on their relative sizes, which of the cranial nerves seems to be the most developed in sheep?
based on their relative sizes, the trigeminal nerve is the most developed. it is responsible for sensation in the face.
why are the sensory nerves in sheep larger than in humans?
b/c senses are the main things sheep use for survival...they also have a larger olfactory bulb and the trigeminal nerve (sensory nerve) is the largest in a sheep brain.
central sulcus
separates frontal and parietal lobes
cerebral cortex
thin layer of gray matter on surface of cerebrum
falx cerebelli
a layer of dura mater that separates cerebellar hemispheres
cerebral lobe located deep within lateral sulcus
optic chaisma
structure formed by the crossing-over of the optic nerves on underside of the hypothalamus
pineal gland
cone-shaped structure attached to upper postereior portion of diencephalon
the posterior part of the forebrain that connects the midbrain with the cerebral hemispheres, encloses the third ventricle, and contains the thalamus and hypothalamus