Biology

The Heart

The heart is about the size of an adult fist. It lies in the middle of the chest between the two lungs. It is a double pump as each side of the heart works separately. Each side of heart pumps blood, the left side pumps blood from the heart to the lungs. The right side pumps blood from the heart to the rest of the body. The heart pumps throughout a person life so it needs to be made up of tissue can that it can ensure it’s efficient throughout a person’s lifespan.

The Circulatory System The circulatory system is also known as the cardiovascular system. This helps to transport supply materials to the cell. Its main functions are to help the maintenance of oxygen to supply to the body. The system consists of the heart, blood and blood vessels.

The Lungs A person’s body consists of 2 lungs. They work to provide us with the oxygen what we need and to remove the carbon dioxide that we create as waste in body. They are made up of a network of tubes that look like a tree in winter. At the end of the smallest tubes are alveoli where gas exchange takes place.

How they all work together

In order to work and create movement, muscles need oxygen. The body's oxygen transport system takes oxygen to the working muscles, through the circulatory and respiratory systems working together. The main workers are the heart, blood and lungs. The whole oxygen transport system works in a cycle.

As we breathe, oxygen enters the lungs and is absorbed into the bloodstream. The heart pumps this oxygenated blood to the working muscles, so that the muscles can produce movement. As the muscles use the oxygen up, carbon dioxide is produced and

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absorbed into the blood. And this de-oxygenated blood is pumped back to the heart then on to the lungs. The lungs get rid of this carbon dioxide.