Human Body Systems By: Andrew Fernandez

The Skeletal System The skeleton protects organs such as the heart, the brain, and the lungs. It also gives us our shape, without it we would be a puddle with organs, tissue, and blood. It helps us move, our muscles are attached to your bones which help you move. When you are born you had about 350 bones, when you’re an adult you will have 206 bones, this is because as you get older your bones connect to make 1 bone.

The Digestive System Every food we eat are weathered down by our digestive system and brought to every part of our body by our circulatory system. The digestive cycle starts in the mouth, where your teeth break it down after it has been chemical changed with saliva. Then after you swallow the food it travels to the stomach. The food passes to the small intestine. The food is broken down more until it goes through the walls of the small intestine on the blood stream. Some thing that can’t be digested goes to the large intestine were minerals and water are brought to the blood stream.

The Respiratory system The respiratory system makes you breath. When we breath, you take in oxygen that we need and give out carbon dioxide that you don’t need. We get air which is sucked in with your mouth or nose.

The Circulatory System The circulatory system is the transport system by which oxygen and nutrients reach the body's, and waste materials are brought away. The heart and lungs are the center of the circulatory system. The heart is positioned behind the ribcage and between the lungs.

The Nervous system In the middle of the nervous system is the brain and the spinal cord. A nerve cell is the basic function of the nervous system. Any time about 5% of the nerve cell are active. The nervous system gives us our senses. When you feel, hear, and taste, the nervous system helps you do it.

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