The cardiovascular system of a mammal is made up of the heart, the blood vessels and the blood. It is a closed, double circulation that carries oxygen, nutrients, hormones, wastes and heat around the body.Types of blood vessel
Blood leaves the heart in arteries, which branch into smaller arterioles and then into capillaries. Capillaries are where substances are exchanged with the tissues. They join to form venules, which join to form veins that return blood to the heart. The structure of each type is covered in a later lesson.Main blood vessels
• Vena cava (superior and inferior): carries deoxygenated blood from the body into the right atrium.
• Pulmonary artery: carries deoxygenated blood from the right ventricle to the lungs.
• Pulmonary vein: carries oxygenated blood from the lungs to the left atrium.
• Aorta: carries oxygenated blood from the left ventricle to the body.
• Coronary arteries: branch from the aorta and supply the heart muscle itself with oxygenated blood.Each major organ has its own artery and vein, for example the renal artery and vein (kidneys) and the hepatic artery and vein (liver). The hepatic portal vein carries blood rich in absorbed nutrients from the intestines to the liver.The pulmonary artery and pulmonary vein are exceptions to the usual rule: most arteries carry oxygenated blood and most veins carry deoxygenated blood, but these two are the other way round. Arteries are defined by carrying blood away from the heart, and veins by carrying blood towards it.
Blood leaves the heart in arteries, which branch into smaller arterioles and then into capillaries. Capillaries are where substances are exchanged with the tissues. They join to form venules, which join to form veins that return blood to the heart. The structure of each type is covered in a later lesson.Main blood vessels
• Vena cava (superior and inferior): carries deoxygenated blood from the body into the right atrium.
• Pulmonary artery: carries deoxygenated blood from the right ventricle to the lungs.
• Pulmonary vein: carries oxygenated blood from the lungs to the left atrium.
• Aorta: carries oxygenated blood from the left ventricle to the body.
• Coronary arteries: branch from the aorta and supply the heart muscle itself with oxygenated blood.Each major organ has its own artery and vein, for example the renal artery and vein (kidneys) and the hepatic artery and vein (liver). The hepatic portal vein carries blood rich in absorbed nutrients from the intestines to the liver.The pulmonary artery and pulmonary vein are exceptions to the usual rule: most arteries carry oxygenated blood and most veins carry deoxygenated blood, but these two are the other way round. Arteries are defined by carrying blood away from the heart, and veins by carrying blood towards it.