biology 🤩

• the circulatory system is an example of an organ system
• the role of the circulatory system is to transport oxygen and nutrients to tissue around the body
• the 3 main factors of the circulatory system are blood, blood vessels and the heart
• blood carries nutrients and oxygen around the body
• blood vessels are what hold the blood
• the heart pumps blood to keep it moving around the body
• the left side of the heart contains oxygenated blood
• the right side of the heart contains deoxygenated blood
• in diagrams the left side of the heart appears on our right
• the heart has four chambers
• the heart has 2 atria and 2 ventricles
• the top chambers of the heart are called atria
• the bottom chambers of the heart are called ventricles
• the purpose of valves is to keep the blood flowing in the right direction
• the vena cava flows into the right atrium
• the pulmonary vein flows into the left atrium
• veins carry blood to the heart
• arteries carry blood away from the heart
• pacemaker cells send small electrical impulses to cause the heart muscles to contract
• arteries and veins can both carry oxygenated or deoxygenated blood
• coronary arteries supply the heart with the oxygen and nutrients it needs to function properly