Heart Dissection

In Biology we dissected a pigs heart. The size of the heart varied between all the groups, some were larger, and some were smaller. The one that my group members and I had was just big enough to comfortably fit into the palm of my hand. It had a semi round shape and a growing point towards the left side because of the Left Ventricle. And if you held it a certain way you could even see the sort of heart shape it had. While holding it in my palms it felt heavier than it was supposed to after rinsing the heart and defrosting the ice it weighed roughly around one to two pounds. The colour on the outside was a reddish-brown and became whiter around the veins. On the inside it was a deep red-brown colour but the arteries and Chordae Tendinae were still a brighter reddish pink colour. The Cordae Tendinae looked like thin pink strings, when looking at them you think that they are wear and easy to break but when you touch or pull on them you realize that they are very strong and sturdy.The AV valves don't look like they seem they are just flaps of flesh but when the heart is whole they are a reliable passage way. The left AV Valve and right AV Valve are approximately the same size. When examining the main chambers and atrium's of the heart you see a difference in size and shape. The Left Ventricle and Right Ventricle believe it or not are the same size but the thicker walls and rounder shape of the left ventricle makes it appear to be bigger. This is because the left ventricle pumps blood to the body and the right ventricle pumps blood to only the lungs. The atrium's are very thin and floppy and act as the passage way for blood to enter, their size is roughly the same. The Pulmonary Trunk is a large blood vessel that prevents the back flow of blood from entering the ventricular chambers, when dissecting the heart if you were to put your finger through the Pulmonary Trunk you would find it being led straight to the atrium, inside the Pulmonary Trunk is a very pink colour it is wide and just slight smaller than the Aorta. The Aorta is the largest artery in the body, and even looks the part. All the blood passed from the heart to the systematic tissues go through the Aorta, the Aorta in this heart had a very large opening and was thick in diameter. 

1. The thing found to be the most surprising was how easy it was to find each part of the heart. I expected that it would be difficult to find all of the parts of the heart because the heart was a pigs so therefore it was smaller, but i was wrong. It turns out that each and every part of the heart is completely visible in its own way!

2. The Atrium's and the Ventricle's differed a lot. The Atrium's were significantly smaller than the Ventricle's because the only jobs the Atrium's have is too collect blood from the veins and deliver the blood to the heart, whereas the Ventricle's must use their squeezing muscle power to pump blood to the arteries above them therefore requiring more strength and power. Ventricle's are structured according to their job they have more muscle, are larger, and is rougher to touch although the Atrium is easier to touch, have less muscle, and are very small.

3. The Left Ventricle is more muscular than the Right Ventricle because the left is responsible for pumping blood to throughout the body whereas the right is only responsible for pumping it to the lungs.

4. As the heart muscle contracts and relaxes, the valves open and shut, letting blood flow into the ventricles and atria at alternate times. When the aortic valve closes and the mitral valve opens, it allows blood to flow from the left atrium into the left ventricle. As the left atrium contracts, more blood flows into the left ventricle. When the left ventricle contracts again, the mitral valve closes and the aortic valve opens, so blood flows into the aorta.The structure of the valves are like flaps, therefore when the heart is whole they attach to form a inlet and makes it easier for the process.