Heart Dissection
Heart Dissection
Sheep have a four-chambered heart, as do humans. By studying a sheep heart you can learn about your own heart at the same time.
1. Identify the right and left sides of the heart. Look closely and on one side you will see a diagonal line of blood vessels that divide the heart. The half that includes all of the apex of the heart is the left side. If you feel the heart, the left half will feel much firmer and more muscular than the right side. The left side of the heart has to be thicker and stronger because it has to pump blood around the whole body whereas the right side only pumps blood to the lungs.
2. Turn the heart so that the right side is on your right. Find the large opening at the top of the heart next to the right auricle. This is the opening to the superior vena cava, which brings blood from the top half of the body to the right atrium (the atria are the top chambers in the heart). A little down and to the left of the large vena cava there is another blood vessel opening. It leads into the right atrium. This is the inferior vena cava, which brings blood from the lower tissues. You can also see another blood vessel next to the left auricle. This is a pulmonary vein that brings blood from the lungs into the left atrium.
3. Sticking straight up from the centre of the heart is the largest blood vessel you can see. This is the aorta, which takes oxygenated blood from the left ventricle to the rest of the body (the ventricles are the lower chambers of the heart). The aorta branches into more than one artery right after it leaves the heart.
4. 4. Behind and to the left of the aorta there is another large vessel. This is the pulmonary artery which takes blood from the right ventricle to the lungs.
Inside of the heart.
1. Insert your scalpel into the superior vena cava and make an incision down through the wall of the right atrium and ventricle. There are membranes which are connected to flaps of muscle by tendons, these are called
Sheep have a four-chambered heart, as do humans. By studying a sheep heart you can learn about your own heart at the same time.
1. Identify the right and left sides of the heart. Look closely and on one side you will see a diagonal line of blood vessels that divide the heart. The half that includes all of the apex of the heart is the left side. If you feel the heart, the left half will feel much firmer and more muscular than the right side. The left side of the heart has to be thicker and stronger because it has to pump blood around the whole body whereas the right side only pumps blood to the lungs.
2. Turn the heart so that the right side is on your right. Find the large opening at the top of the heart next to the right auricle. This is the opening to the superior vena cava, which brings blood from the top half of the body to the right atrium (the atria are the top chambers in the heart). A little down and to the left of the large vena cava there is another blood vessel opening. It leads into the right atrium. This is the inferior vena cava, which brings blood from the lower tissues. You can also see another blood vessel next to the left auricle. This is a pulmonary vein that brings blood from the lungs into the left atrium.
3. Sticking straight up from the centre of the heart is the largest blood vessel you can see. This is the aorta, which takes oxygenated blood from the left ventricle to the rest of the body (the ventricles are the lower chambers of the heart). The aorta branches into more than one artery right after it leaves the heart.
4. 4. Behind and to the left of the aorta there is another large vessel. This is the pulmonary artery which takes blood from the right ventricle to the lungs.
Inside of the heart.
1. Insert your scalpel into the superior vena cava and make an incision down through the wall of the right atrium and ventricle. There are membranes which are connected to flaps of muscle by tendons, these are called