The Circulatory System
A wall of muscle separates the hearth into two parts called chambers. Both chambers work at the same time and act like pumps. Each chamber has an upper part called the atrium ans a lower part called the ventricle. The right pump sends oxygen-poor blood and carbon dioxide-rich blood to the lungs.
In the lungs, the blood gets rid of the carbon dioxide and takes on a fresh supply of oxygen. The blood with carbon dioxide is bluish in color and the blood with oxygen is bright red.
The left pump receives the bright red blood from the lungs and send it to all parts of the body trough the main blood vessel called the aorta. This complete the pumping cycle.
Explanation:
The human heart has two main chambers, divided into two parts, responsible for the distribution of blood in the circuits known as major and minor circulation.
The major circulation involves the route that the blood, pumped by the heart, takes through the whole body, carrying the oxygen-rich blood —arterial with red blood— through the arteries, to then return as non-oxygenated or venous —bluish— blood through the veins, reaching the heart again.
The minor circulation goes from the heart to the lungs and from these to the heart. The right ventricle sends the venous blood through the pulmonary arteries to the lungs, and returns through the pulmonary veins to the heart.
A resume of the complete path of the blood in the body is
:
The blood reaches the right atrium through the vena cava, enters the right ventricle and from there goes to the lungs, through the pulmonary arteries, the only arteries that carry venous blood.
The lungs send the blood to the left atrium, through the pulmonary veins —the only ones that carry arterial blood— it goes into the left ventricle and from there it is pumped to the whole body through the aorta artery, which distributes it throughout the arterial tree.
