Sheep Brain Dissection Sheep Brain External Anatomy Procedure

1. Set the brain down so the flatter side, with the white spinal cord at one end, rests on the dissection pan. 2. Notice that the brain has two halves, or hemispheres. 3. Identify the cerebrum (frontal , temporal, parietal, and occipital lobes) and the cerebellum 4. Turn the brain over. 5. Identify the medulla, pons, midbrain, and olfactory bulbs. 6. Find the olfactory bulb on each hemisphere. These will be slightly smoother and a different shade than the tissue around them. The olfactory bulbs control the sense of smell. The nerves to the nose are no longer connected, but you can see nubby ends where they were. The nerves to your mouth and lower body are attached to the medulla; the nerves to your eyes are connected to the optic chiasm.

Sheep Brain Dissection: Internal Anatomy

1. Place the brain with the cerebrum facing up. 2. Use a scalpel to slice through the brain along the center line, starting at the cerebrum and going down through the cerebellum, spinal cord, medulla, and pons. 3. Separate the two halves of the brain and lay them with the inside facing up. 4. Identify the corpus callosum, medulla, pons, midbrain, and the place where pituitary gland attaches to the brain. (In many preserved specimens the pituitary gland is no longer present.) 5. Use your fingers or a teasing needle to gently probe the parts and see how they are connected to each other. Sheep Brain Dissection: 1. Frontal Lobe 2. Temporal Lobe Internal Anatomy 3. Occipital Lobe 4. Brainstem 1. Identify the 5. Midbrain following 6. Pons structures on the 7. Medulla brain and quiz each 8. Cerebellum 9. Cerebrum other on their 10.Corpus callosum functions. 11.Pituitary gland 12.Hypothalamus 2. Use the diagram on 13.Thalamus the next page to 14.Spinal cord help identifying the 15.Olfactory bulb structures. 16.Hippocampus 17.Pinal gland 18.Transverse fissure

View Cerebrum and Cerebellum under the microscope 1. Slice off a very thin section of the cerebrum and put it on a slide, covering it with a drop of water and a coverslip. Look at it under 100X and 400X magnification. 2. Follow the same procedure with a section of the cerebellum, then compare and contrast the two. Dissection Clean Up 1. Place brain in bag and as many of the little pieces. Then put in big trash bag. 2. Rinse and place utensils in front sink. 3. Rinse the tray and blue cutting sheet. Clean both with Lysol wipes or spray. 4. Place tray and blue sheet on paper towel on front counter to dry. 5. Clean tables with Lysol wipes or spray. 6. Make sure floor around your area is cleaned. 7. Wash hands