In this assignment I will outline the anatomy and physiology of these three body systems; The Cardiovascular system, The Respiratory system and The Digestive system.
The Cardiovascular System
The cardiovascular system, also known as the circulatory system, consists of the heart, blood vessels and approximately 5 litres of blood. 55% of the blood is straw coloured yellow and 45% of the blood is made up of red and white blood cells and tiny particles called platelets. This system is powered by the heart and is responsible for transporting oxygen, nutrients, hormones and cellular waste throughout the body. Oxygen is very important to blood and to the cells as it is necessary for cell growth and energy. Red corpuscles (red blood cells) transport oxygen to the body’s cells and carry away carbon dioxide from the cells. Inside the blood there is plasma. The plasma carries minerals, vitamins, sugar and other foods to the body’s cells.
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The heart is found in the thorax (the chest) beneath the sternum. In an adult the heart will weigh around 300g and is approximately the size of a fist and consists mainly of cardiac muscle tissue. The cardiac output is five litres of blood per minute but this can rise up to 20 litres a minute during/after exercise. Blood is supplied to the heart by the coronary arteries and veins. These also supply oxygen and nutrients as well as collecting carbon dioxide and waste. The heart rate in an adult is between 60-80 beats per minute. This can rise to 180 beats per minute if the person took part in exercise. The heart rate of a baby can be 140-160 beats per minute.
The heart has four chambers, the two top chambers are called atria and they receive blood from the veins. The two bottom chambers are called the ventricles and they pump blood out through the arteries to the lungs and then around the rest of the body. The entry and exit points into the ventricles contain valves which make