THE CIRCULATORY SYSTEM
FUNCTION The circulatory system is an organ system that passes nutrients, gases, hormones, blood cells… to and from cells in the body to help fight diseases and help stabilize body temperature and pH to maintain homeostasis.
BLOOD SYSTEM The blood system is formed by the blood, the blood vessels and the heart.
THE BLOOD Is a liquid viscuous, dense and red circulating in the blood vessels. Is formed by one liquid part called plasma. In the plasma there are three kinds of cells: erythrocytes, leukocytes and platelets. The blood carries food, oxygen, cell waste and hormones. The blood defends the body. The blood regulates the body temperature.
THE PLASMA Is a light yellow transparent liquid. In it float the blood cells. It’s formed by 90% of water 7% of proteins 3% mixture of molecules
ERYTHROCYTES The erythrocytes carry oxygen from the lungs at all the organs and tissues of the body. They are red because they contain hemoglobin. The erythrocytes are the most abundant cells of the body. They haven’t got nucleus.
LEUKOCYTES The leukocytes are blood cells with nucleus and they are bigger than the erythrocytes. Their function is defend the body. There are three types of leukocytes: Granulocytes Lynphocytes Monocytes
PLATELETS They are much smaller than the leukocytes and the erythrocytes and they haven’t got nucleus. The mission of the platelets is the coagulation of the blood when a blood vessel brokes.
BLOOD VESSELS Arteries: they’re the vessels that transport the blood from the heart to the organs. Veins: they’re the vessels that transport the blood from the organs to the heart. Capillaries: they’re the vessels that join the arteries with the veins.
THE HEART The heart is an organ that pumps the blood through the circulatory system. It allows the blood is always in movement. It’s formed by the myocardial, a cardiac muscular tissue. The heart is made up of four chambers, the two large are the ventricles and the other two are called auricles. They are connected by valves. Tricuspid valve. Mitral valve.
CIRCULATION CIRCUIT There’re two types of circuits: Pulmonary: this circuit leads the blood to the lungs for oxygenate it. Systemic: this circuit sends the blood filled of oxygen and nutrients to all the cells of our body.