Obtain a sheep brain and observe the following before making any cuts:
 Review all external features (brain regions, major gyri and sulci, olfactory bulb and optic nerves)
 Observe any remnants of the meninges- (the dura mater may still be present, the pia mater is present)
Carefully remove the dura mater if it is still present. Cut it free carefully so the brain is not damaged as you remove it.
Cut the brain in to two equal sagittal sections. Use the diagram of the sagittal section to locate, observe and review the function of the following structures on the sheep brain sections:
1. Cerebrum a. corpus callosum (genu, body, splenium) b. septum pellucidum c. lateral ventricles (with choroid plexus) d. interventricular foramen e. calcarine sulcus f. cingulate gyrus g. parietal-occipital sulcus h. fornix
2. Diencephalon i. thalamus j. hypothalamus k. epithalamus (pineal body) l. third ventricle m. intermediate mass n. choroid plexus o. mamillary body p. infundibulum (with hypophysis attached)
3. Brainstem q. midbrain
 cerebral peduncles
 cerebral aqueduct
 corpora quadrigemina (superior and inferior colliculi) r. pons
 fourth ventricle (posterior) with choroid plexus s. medulla oblongata
 pyramids
4. Cerebellum t. arbor vitae u. folia and fissures
5. Additional Structures v. optic chiasma w. central canal (spinal cord) x. gray and white matter y. olfactory bulbs z.
diaphragma sella aa.
anterior commissure bb.
posterior commissure
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1. What are the basal ganglia (nuclei) and what is their main function?
2. What cerebral lobe is deep to the lateral sulcus? What is it’s function?
3. Differentiate between the following types of fiber tracts: a. projection fibers  b. association fibers  c. commissural fibers ( give two examples (regions) of this type of fiber 
4. What structure is a large commissural tract connecting the two cerebral hemispheres?
5. What is the function of the choroid plexus? Where can you find it?
6. What is the function of a dural sinus?
7. In what space does the CSF flow? How is it emptied?
8. With what cerebral lobe is the cingulate gyrus associated? What is the function of this lobe?
9. What is the septum pellucidum?
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