A Medical Guide to the Circulatory Sytem - For Kids!

Your body has many systems that let if function through the day. Each is very important and the circulatory system is certainly no exception. The circulatory system is also sometimes called the cardiovascular system and it has three parts: blood, blood vessels and the heart. Human Heart.

Its purpose is to deliver oxygen from lungs to the cells in the body. Without oxygen, these cells would die and so would we. The central hub of the circulatory system is the heart, a fist-sized organ filled with four chambers and a number of valves. The heart functions through involuntary muscular activity – which means you can’t stop it from beating like you can stop your hand from writing or your feet from running. The heart pumps the blood through the blood vessels. During its travels, the red blood cells absorb oxygen and carry it through arteries. The reason arteries appear red is because they are full of oxidized blood, which is red.

After the blood cells bring the oxygen and give it to the other cells, the deoxidized blood cells return to the heart through veins. Veins appear a bluish green color because deoxidized blood is blue. The reason you never see blue blood, even if you cut a vein is because as soon as the blood leaves your body, it mixes with the oxygen in the air and turns red again. Also in the blood are antibodies that fight infections. Without the blood flowing to different parts of the body, the antibodies would never get where they need to go to fix your injuries.

There is a lot more to learn about the circulatory system, so why not check out these other neat sites!

Overview of the Circulatory System

The Heart

Lesson Plans/Teacher Resources




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