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• the thorax is the top part of your body its separated from the lower part by the diaphragm
• oxygen diffuses out the alviolus (high concentration) into the blood (low concentration)
• the circulatory system carries food and oxygen to the body cells and removes waste products
• the circulatory system is made up of the heart, blood vessels and blood
• humans have a double circulatory system
• in the first one, the right ventricle pumps deoxygenated blood to the lungs to take in oxygen. the blood then returns to the heart
• in the second one the left ventricle pumps oxygenated blood all around the other organs of the body
• the heart contracts to pump blood all around the body
• on heart diagrams left and right are the other way round
• the bottem bit of the heat is called the ventricals
• the top bits of the heart are called the atriums
• on the left side the top vein is called the aorta
• on the left side the bottom vein is called the pulmonary vein
• on the right side the top vein is called the pulmonary artery
• on the right side the bottom vein is called the vena cava
• your resting heart rate is controlled by a group of cells in the right atrium that act as a pacemaker
• the pace maker produces the electrical impulses that control the heartbeat
• an artificial pacemaker can be implanted if the patent has an irregular heartbeat
• arteries- carry blood away from the heart