Dissection of the Heart

3/4/15- 3/5/15

Focus of Procedure:

-Identify and observe the parts of the heart and demonstrate an understanding of the blood flow from the lungs, through the heart and out to the body.

Materials:

-scalpel, tweezers, teaser needle, and plastic bag.

Procedure:

1) Remove the heart from the plastic bag and study the parts of the heart.
2) Using a scalpel, remove any excess fat surrounding the heart. Take pictures of the heart while it is intact.
3) Using a scalpel, cut the heart in half horizontally, dividing the heart into two halves. Notice the left and right ventricles. The right ventricle is dyed blue and is the un-oxygenated side. The left ventricle is dyed pink/red and is the oxygenated side. Take a picture of the heart cut in half, specifically the ventricles. Pay special attention to the difference in thickness of the walls in the heart. This thick wall is called the septum.
4) Discuss the the heart's importance to the blood flow in the body. Understand the cycle of blood flow from lungs to heart and heart to body.
5) Using a teaser needle, clean out the extra dried blood (blackish colored and stuck inside the ventricles) then try to identify the chordate tendineae fibers within the heart. Do this carefully as the fibers are extremely delicate.
6) Once you have finished clearing out the ventricles take a picture of the inside of the ventricles on each halve of the heart. Take pictures of the chordate tendineae fibers if possible.
7) Now using your scalpel, cut each halve of the heart down the middle or vertically. This will allow you to have a better view and understanding of the ventricles and chordate tendineae.
8) Finish taking any pictures of the heart and then place the heart back into the plastic bag.

Data and Observations:
Samara's heart was fairly small yet in very good condition. There was a fair amount of fat covering the heart, but once that was removed, I had a better view of her heart. After cutting the heart in half, I was able to view the ventricles. The walls of the heart were thicker around the left ventricle, which is the oxygenated side; and the walls around the left ventricle (the un-oxygenated side) were thinner. This is because the arteries are smaller than the veins, which allows for rapid transfer of blood back to the heart. Semara's ventricles looked very healthy and I was clearly able to see the difference between her left and right ventricles. I had trouble finding the chordate tendineae fibers, but overall Semara had a very healthy heart. All pictures are shown below.

Conclusion:
Dissecting the heart was fairly easy and it gave me a better understanding of the circulatory system. I was able to physically hold the heart in my hands and visually see the different parts of the heart, which gave me a better understanding of the blood flow through the heart and out to the body. I enjoyed dissecting the heart because it was very cool to see the inside of the heart and how this organ functions.