1. Sheep Brain Dissection

2. Introduction Today we will be dissecting a sheep brain In order to proceed today you will need to make sure that you will be able to work safely in the classroom This means you will need close toed shoes, safe clothing and hair ties You will also need a full set of lab safety equipment Make sure each person in your lab group has lab safety goggles, gloves and any other equipment that you may require

3. Introduction to the Sheep Before we pass out our sheep brains, lets get to know our sheep! Sheep are ruminant mammals that are commonly found on farms and pastures They are often kept for their valuable wool and their meat Their main predators are large mammals such as wolves or bobcats They often stay in a pack to ensure safety in numbers They are often portrayed as unintelligent animals due to their compulsion to follow the herd However sheep have been seen to have basic problem solving skills and advanced memory formation skills

4. Mater Ok, lets start the fun part! Everyone come forwards and grab a sheep brain There might be the dura, arachnoid and pia mater on your brain If that is the case your brain will look something like this…

5. Removal Mater Use your scalpel, scissors and your forceps to remove the mater Do this very carefully in order to make sure that your brain is not damaged in the process

6. The Brain Now place your brain down on your dissecting tray to be able to look at it and draw it from different angles Remember, your brain needs to be drawn from two different angles in your lab

7. Moving the Cerebellum Now lightly press down on the cerebellum Locate the “hills” that are formed by the superior and the inferior colliculi The small bump above them is the pineal body

8. Separation of the Hemispheres There may be a small amount of meninges that are holding the cerebral hemispheres together You can separate them by pulling the hemispheres lightly apart and cutting them with a scalpel, scissors or a probe

9. Corpus Callosum Using your hands pull apart the brain at the cerebral hemispheres This will allow you to look down into the longitudinal fissure of the brain that separates the hemispheres Here you can see the corpus callosum

10. Now… Lets Cut! Taking a scalpel with firm pressure, cut down the center of the longitudinal fissure Use pressure to create as few clean cuts as possible This will create a clean dissection and allow us to see more structures!

11. Find the Ventricle! Use the probe or a pin to find the hollow space that is the lateral ventricle Find the lateral ventricle and measure it for length and height

12. Label the Structures Now, you might have to use your notes and other materials to find the different sections of the brain listed on your lab Use a pin or a probe to identify them and be sure to notify Mr. Owdij when you have located all or most of them! You will be given points based on if you can find them or not… so look hard!