Sara Dressman ’15
Human Biology B students had the opportunity to dissect sheep brains in class. This marks a strong difference between Human Biology A and Human Biology B: where Human Biology A is focused on memorization and learning the functions of many body systems, Human Biology B is dependent on more hands-on learning. As disgusting as dissecting a brain may sound to many students, this was a very valuable experience. Getting to see a concrete version of what we are learning gives us better spatial references as to what these parts actually look like. A common complaint of many of the students was that it was difficult for them to identify some parts because unlike the book diagrams, just about everything was one of two colors: gray or white.
First, students began the assignment by examining the exterior portion of the brain and identifying its parts. These parts, such as the cerebellum or the medulla oblonga. The cerebellum controls that controls the body’s basic functions like breathing and swallowing, while the medulla oblonga connects the brain to the spinal cord. Second, students removed the dura mater. The dura mater is a protective covering over the surface of the brain that appears shiny, like a fish scale. Third, after cutting through the protective layer, students took a cross-section of the brain by cutting it down the middle to examine the brain’s interior structure. The cross-section allowed students to see parts such as the corpus callosum. The corpus callosum connects the right and left hemisphere of the brain. Students also identified the thalamus, which is the center for interpreting sensory information(skin, eyes, ears, etc.) and the ventricles, which circulate cerebrospinal fluid to cushion the brain from damage).
Many students ended up enjoying this dissection segment although many were originally opposed to the idea of cutting open a brain. Hands-on activities like this help students get a real grasp of the material that they are studying.