Circulatory Sytem

• The circulatory system is the body's transport system that carries substances around the body.
• Organs involved in the circulatory system include the heart, blood vessels, and blood.
• Gases transported through the circulatory system include oxygen for respiration to body’s cells and carbon dioxide, a waste gas produced by respiration and taken away from body’s cells.
• There are two types of blood: oxygen-rich blood and oxygen-poor blood.
• Blood travelling to cells is high in oxygen and low in carbon dioxide, while blood travelling away from the body’s cells is low in oxygen and high in carbon dioxide.
• The heart, made up of muscle, pumps blood around the body and has both types of blood separate.
• Coronary arteries are blood vessels outside of the heart that carry oxygen-rich blood.
• The heart has valves, which act like doors opening in one way, to prevent blood from flowing backwards.
• The heart beats in a sequence of contraction and relaxation, causing a lub-dub sound: Lub (entrance ventricles valves close) and Dub (exit ventricles valves close).
• Pulmonary circulation is the blood flow from heart to the lungs to get oxygen.
• Systemic circulation is the blood flow from heart to cells to distribute oxygen to cells and bring back carbon dioxide wastes to the heart.
• Blood carries oxygen and nutrients needed for body cells, collects body’s wastes and carbon dioxide, and has red blood cells (RBCs), white blood cells (WBCs), and platelets.
• Blood vessels include arteries, which carry blood away from heart, and veins, which carry blood back to heart.
• Arteries are elastic and allow stretching, contraction, and pushing blood along.
• The aorta is the largest artery, while the arterioles are the smallest.
• Veins have valves that stop blood in veins from going in the wrong way.
• The vena cava is the largest vein, while the venules are the smallest.
• Capillaries exchange materials between blood and other cells, with the wall of a capillary being one cell thick and linking with arteries and veins.
• The circulatory system is made up of the heart, blood vessels (arteries, veins & capillaries) and blood.
• Blood carries oxygen to cells and removes waste products from them
• Arteries carry blood away from the heart
• Arteries carry blood away from the heart under high pressure
• Blood carries oxygen to all body tissues and removes carbon dioxide produced by respiration.
• Hormones can be transported through the bloodstream to target organs or glands.
• Blood also transports nutrients absorbed during digestion around the body.
• Veins carry blood towards the heart
• Veins return deoxygenated blood back to the heart
• Veins carry blood back towards the heart
• Capillaries connect arteries and veins
• Capillaries allow substances to pass into or out of the blood
• Veins have thin walls as they do not need to cope with high pressures like arteries
• The circulatory system is made up of the heart, arteries, veins, capillaries, and blood.