The Human heart has many complicated processes. Dissecting a sheep’s heart can help to provide an active, firsthand learning experience that allows to illustrate what has been previously heard and read. The sheep heart and a human heart share the same function and purpose, which is to keep the body alive by continually circulating blood around the body. Like a human heart, a sheep’s heart contains two atria and two ventricles. These four chambers work together to pump deoxygenated blood to the lungs and oxygenated blood to the rest of the body.
The important reason for carrying out this experiment is to examine and understand the structural features of the heart which will help us to understand and to appreciate how the heart operates. The main purpose behind dissecting a lamb’s heart was to understand the different functions that each part of the heart performs from the atria at the top of the heart to the ventricles at the bottom, as well as why each section is so important to a heart functioning properly and correctly. To begin this experiment we had to identify the external parts of the heart. Starting with the right and left side of the heart.
This was done by looking for blood vessels that divided the heart in half. After observing each side it was easy to determine the left side was stronger. The reason is because it has the important job of regulating blood flow around the majority of the body. The next task required the groups to examine the darker tissue, also known as the auricles. This then allowed us to identify the superior vena cava that directs blood to the right atrium at the top half of the heart. A probe was then used to locate the inferior vena cava that brings blood to the right atrium from the lower tissues.
After finding the left auricle, it was possible to see the pulmonary vein, which brings blood from the lungs to the left atrium. The final part of the external anatomy observation was to locate the largest blood vessel, the aorta. The aorta job is to transports oxygenated blood from the left ventricle to the rest of the body and the pulmonary artery, which takes blood from the right ventricle and transports it to the lungs. After beginning to examine the internal anatomy of the heart, it was necessary to cut through the right hand side of the heart using either the dissecting scissors to reveal the tricuspid valve.
After making this incision, the papillary muscles could then be seen. When using the probe in the pulmonary artery, small membranous pockets called the pulmonary semilunar valve also had to be identified. The probe was finally inserted into the aorta to carefully examine inside, looking for the aortic semilunar valve, which has the responsibility of preventing the backflow of blood into the left ventricle. The aim of this experiment was to investigate the structure and functions of a lamb’s heart and to identify the similarities and differences between it and a human heart.
After intense analysis of the heart, a further understanding of each structure was achieved. The heart has two sides, the right side of the heart received deoxygenated blood via the vena cava from the superior and inferior sides of the body. This deoxygenated blood travels through the vena cava into the right atrium, down the tricuspid valve into the right ventricle. When the ventricles contract the deoxygenated blood in the right ventricle is pumped through the pulmonary artery passing the semi-lunar valve. This deoxygenated blood then travels to the capillaries of the lungs where they exchange waste products such as carbon dioxide for oxygen.
The blood is not oxygen-rich therefore oxygenated. The oxygenated blood then travels from the capillaries of the lungs to the pulmonary vein which leads to the left atrium of the heart, once the oxygenated blood is in the left atrium it is pushed through the bicuspid valves into the left ventricle when it is then further pumped though the aortic semi-lunar valves into the aorta where it is distributed to the rest of the body where oxygen is required. The dissection was a success, all the chambers, vessels and valves were identified. This dissection was beneficial in connecting previous learned information.