File Name: the human heart anatomy and circulation .zip
The Circulat ory System. Location of the Heart. The center of the circulatory system is the heart , which is the main pumping mechanism.
Structure of the Heart
The human heart is a four-chambered muscular organ , shaped and sized roughly like a man's closed fist with two-thirds of the mass to the left of midline. The heart is enclosed in a pericardial sac that is lined with the parietal layers of a serous membrane. The visceral layer of the serous membrane forms the epicardium. Three layers of tissue form the heart wall. The outer layer of the heart wall is the epicardium, the middle layer is the myocardium , and the inner layer is the endocardium. The internal cavity of the heart is divided into four chambers:.
The general structure of the circulatory system of the rat is almost identical to that of humans. Pulmonary circulation carries blood through the lungs for oxygenation and then back to the heart. Systemic circulation moves blood through the body after it has left the heart. You will begin your dissection at the heart. It is important that you do not cut the vessels as you carefully remove any muscles and surrounding tissue to expose them.
How does the heart work? What does it do? What is it composed of? How do you examine it? This article offers cardiac anatomy and physiology in a nutshell. The heart is a complex organ that pumps blood through the body with an intricate system of muscle layers, chambers, valves and nodes.
The cardiovascular system is a closed system if the heart and blood vessels. The heart pumps blood through a closed system of blood vessels. Blood vessels allow blood to circulate to all parts of the body. The vital importance of the heart is obvious. If one assumes an average rate of contraction of 75 contractions per minute, a human heart would contract approximately , times in one day, more than 39 million times in one year, and nearly 3 billion times during a year lifespan. Each of the major pumping chambers of the heart ejects approximately 70 mL blood per contraction in a resting adult. This would be equal to 5.
The pulmonary circulation is the portion of the circulatory system which carries deoxygenated blood away from the right ventricle, to the lungs , and returns oxygenated blood to the left atrium and ventricle of the heart. The vessels of the pulmonary circulation are the pulmonary arteries and the pulmonary veins. A separate system known as the bronchial circulation supplies oxygenated blood to the tissue of the larger airways of the lung. Deoxygenated blood leaves the heart, goes to the lungs, and then re-enters the heart; Deoxygenated blood leaves through the right ventricle through the pulmonary artery. From the right atrium, the blood is pumped through the tricuspid valve or right atrioventricular valve , into the right ventricle.
Location, size and shape of the heart. The chambers of the heart. The circulation system of the heart. The heart's valve anatomy. Coronary arteries and veins.
Anatomy of a Human Heart
Make sure that your printout includes all content from the page. If it doesn't, try opening this guide in a different browser and printing from there sometimes Internet Explorer works better, sometimes Chrome, sometimes Firefox, etc. The vital importance of the heart is obvious. If one assumes an average rate of contraction of 75 contractions per minute, a human heart would contract approximately , times in one day, more than 39 million times in one year, and nearly 3 billion times during a year lifespan.
Your heart does a lot of work to keep the body going. Each day, the average human heart beats about , times, pumping 2, gallons of blood through the body. In fact, the heart does more physical work than any other muscle over a lifetime.
Его доказательства, его программы всегда отличали кристальная ясность и законченность. Необходимость убрать пробелы показалась ей странной. Это была мелочь, но все же изъян, отсутствие чистоты - не этого она ожидала от Танкадо, наносящего свой коронный удар. - Тут что-то не так, - наконец сказала .
Это как будто деление на ноль. - Что.
Но если бы знала, сколько вы мне за него предложите, то сохранила бы это кольцо для. - Почему вы ушли из парка? - спросил Беккер. - Умер человек.
Стратмор покачал головой, отказываясь верить тому, что услышал.