Heart Anatomy

The heart is a major factor in circulating blood throughout the body and keep the body alive. The heart pumps around 7,000 liters though the body a day. Thats a huge amount for such a small organ. Around the heart there are vessels and viens that help with blood circulation, this system is called the cardiovascular system. There are two different circuits called the pulmonary and the systemic circuit. The pulmonary circuit is when the oxygen depleted blood is sent to the lungs to pick up oxygen and drop off carbon dioxide. The other circuit is called the systemic circuit and it is when oxygenated blood and nutrients are sent throughout the body cells and helps to remove wastes. The inside of the heart is divided into four chambers. The top chambers, the left and right atrium, have think walls that recieve blood returning to the heart. The lower chambers are the left and right ventricles and they force blood into the arteries.There are two septums in the heart called the interatrial septum and the interventrical septum. The interatrial septum seperates the left and right atrium and the interventricular septum seperates the two ventricles. The left and right atriums communicate to each other by a opening called the atrioventricular orifice and it is guarded by the av valve.
The right atrium recieves blood from two large veins called the superior,and inferior vena cava. The blood these veins return is low oxygen and from the tissues. As the blood travels through the heart it goes to the pulmonary trunk which is the only place for it to exit. While in the trunk it divides into either the left or right pulmonary arteries that eventually lead to the lungs. At the bottom of the trunk is the pulmonary valve. When the right ventricle contracts the valve opens and blood runs through. The left atrium receives the blood from for four pulmonary veins. Two are in each lung.

In class we had a lab when we disected a pig heart and viewed the different arteries and how they transported blood throughout the heart. From the lab I learned that the heart is a lot larger than I thought and is also much more complex than I gave it credit for. Down below are pictures of the disected pig heart.