Cardiovascular (Circulatory) System
The cardiovascular system consists of the heart, blood vessels such as veins and arteries, as well as almost 5 liters of blood traveling throughout the body. This system pumps the blood to every part of the body in order for it to maintain proper use, but it also transports cellular waste, hormones, nutrients, and oxygen throughout the body. On this page, this system will only consist of heart anatomy and physiology. We will not begin to explain each and every artery and vein, although there is a description of the main ones at the following source.
Heart - A closed-fist sized muscular organ that serves to take in deoxygenated blood from the veins and send it through to the lungs in order for it to become oxygenated and sent throughout the body via arteries. The heart is located in the thoracic cavity intermediate, or medial, to the lungs and posterior to the sternum. There is a sac of fluid that surrounds the heart, known as the pericardial sac, and is composed of pericardium. This sac serves to lubricate the heart from causing any friction between the heart and other organs. The specified important regions of the heart include the following: the Aorta, the Vena Cava (Superior and Inferior), the right and left atria, the tricuspid and bicuspid (Mitral) valves, the right and left ventricles, and the pulmonary arteriy as well as veins.
The heart consists of three outer layers: Epicardium, Myocardium, and Endocardium (listed from superficial to deep).
The different sections of the heart (i.e. aorta, ventricles, atria) may have varying thickness of the heart wall. The thickness depends on the distance the blood will be pumped; if the distance is short, then the wall will be relatively thin, and vice versa for further traveling and the wall being thick.
- Epicardium - The outermost layer of the heart and is just another name for the visceral layer of pericardium. The epicardium is a thin layer of serous membrane that lubricates and protects the outside of the heart.
- Myocardium - The muscular middle layer of the heart that contains the cardiac muscle tissue. The myocardium makes up a majority of the heart wall and holds responsibility for pumping blood.
- Endocardium - The innermost layer of the heart that contains simple squamous epithelial tissue. The endocardium makes up the inside wall of the heart and serves a function of preventing blood from sticking within the heart, then preventing potential blood clots.
The different sections of the heart (i.e. aorta, ventricles, atria) may have varying thickness of the heart wall. The thickness depends on the distance the blood will be pumped; if the distance is short, then the wall will be relatively thin, and vice versa for further traveling and the wall being thick.
The flow of blood throughout the heart alone serves as very important information. This flow should never change, but if it does then a medical professional should be informed immediately. The heart beat "noise" commonly referred to as "Lub-Dup" is due to the closing and opening of the different valves within the heart. If that beat is irregular, there is also likely complication that need be checked out.
The Flow of Blood
First, the oxygenated blood that is used up becomes deoxygenated and the thousands of miles of veins carry it back toward the heart. These veins take the blood to one of two places: the superior vena cava or the inferior vena cava. The blood returning from the inferior sagittal plane of the body enter the inferior vena cava and vice versa with the superior sagittal plane. Once entered into the heart, the blood flows to the right atrium. There is a separation between the right atrium and right ventricle known as the tricuspid valve. After crossing the tricuspid valve, the blood enters the right ventricle. There is another valve following the right ventricle, known as the pulmonary valve. The pulmonary valve directs the blood into the pulmonary trunk and pulmonary artery, and at this point the blood is still deoxygenated. Once the blood travels through the pulmonary artery, it is passed through the lungs and capillary beds to transfer the carbon dioxide into oxygen, then becoming oxygenated. Once the oxygenation has completed, the blood then returns to the heart once more. The blood returns through the pulmonary veins and enters the left atrium. After leaving the left atrium, the blood travels through the mitral valve (or commonly known as the bicuspid valve) and enters the left ventricle. This oxygenated blood has to continue moving through the heart until sent throughout the body where it is needed. After leaving the left ventricle, the blood passes through the aortic valve, enters the aortic trunk and is sent throughout the body via arteries. The flow of blood maintains a repetitive cycle
The Flow of Blood
First, the oxygenated blood that is used up becomes deoxygenated and the thousands of miles of veins carry it back toward the heart. These veins take the blood to one of two places: the superior vena cava or the inferior vena cava. The blood returning from the inferior sagittal plane of the body enter the inferior vena cava and vice versa with the superior sagittal plane. Once entered into the heart, the blood flows to the right atrium. There is a separation between the right atrium and right ventricle known as the tricuspid valve. After crossing the tricuspid valve, the blood enters the right ventricle. There is another valve following the right ventricle, known as the pulmonary valve. The pulmonary valve directs the blood into the pulmonary trunk and pulmonary artery, and at this point the blood is still deoxygenated. Once the blood travels through the pulmonary artery, it is passed through the lungs and capillary beds to transfer the carbon dioxide into oxygen, then becoming oxygenated. Once the oxygenation has completed, the blood then returns to the heart once more. The blood returns through the pulmonary veins and enters the left atrium. After leaving the left atrium, the blood travels through the mitral valve (or commonly known as the bicuspid valve) and enters the left ventricle. This oxygenated blood has to continue moving through the heart until sent throughout the body where it is needed. After leaving the left ventricle, the blood passes through the aortic valve, enters the aortic trunk and is sent throughout the body via arteries. The flow of blood maintains a repetitive cycle