Brain Dissection

In our brain dissection (depicted in the images below), we first located external structures on the brain. We located the cerebrum - pinned in yellow - which is associated with higher brain functions like thought and action. Then, we located the cerebellum - pinned in green - which coordinates the body's voluntary movements. We also located the brain stem - pinned in red - which controls the flow of signals between the brain and the body. Lastly, to give the brain an orientation, we labelled the anterior - pinned in white - and the posterior - pinned in black. Myelin, an important part of neurons are not visible to the naked eye so we could not see them in this dissection; however, it is important to note that their function is to insulate the axon of neurons and increase the speed at which impulses move along the axon. Below is an image from the dissection with the colored pins in it and a drawing of what it looked like to me. 

Once we cut through the corpus callosum - pinned in red - we could see the two hemispheres of the brain side by side, which made it easier to locate the internal structures of the brain. The corpus callosum is essentially a dense connection of nerves that passes information between the two hemispheres of the brain. Now it was possible to locate the thalamus - pinned in black - which functions as a router that integrates the information that sensory neurons take in. We could clearly see the optic nerve - the lower white pin - which hung off the brain a little bit and takes the input we take in from the eyes to the brain so it can be converted to vision. The medulla oblongata - pinned in green - was also clear here, and it's important to the brain as it regulates respiration and blood circulation. We located the pons - pinned in blue - as it controls our breathing and the communication of different parts of the brain with each other. The midbrain - pinned in yellow - controls our vision, motor skills and hearing, and is in charge of temperature regulation. Lastly, we found the hypothalamus - the upper white pin - which maintains the body's homeostasis and circadian rhythm. In the images below, you can see one hemisphere of the brain with the pins in it, my drawing of that hemisphere, and then what the two hemispheres of the brain look like side by side.

Lastly, we made a cross sectional cut in the cerebrum so that we could see what white matter and gray matter look like in the brain. Below are two pictures: one showing the cross section from the brain we dissected, and the second showing my drawing of the cross section. The white matter here appears whitish and the gray matter appears pinkish. 

For more information on specific parts of the brain and where they are located in the brain, please see my previous post about our Clay Brain Activity. We used the Clay Brain model we made in this activity to help us find the parts of the brain during this dissection and it proved to be an excellent resource!