The nervous system
The nervous system connects your brain to send and receive information about what is going on in the body and around it. You have billions of nerve cells, or neurons which join together to make nerves. It's looks like little strings covered in a fat called myelin. Myelin helps the messages, which is actually called impulses, travel to and from the brain quicker.
The Skeletal System
The skeletal system is the thing that keeps your body from looking like a pile of mush. We are born with 270 bones and, believe it or not, we have 206 by the time we're adults. Where do you think those extra bones go?
The Respiratory System
Another function our body does is breath:We take in oxygen and release carbon dioxide. The oxygen we breath in is carried into our blood which travels around our body to supply or give oxygen to different organs. Here is a diagram showing the nose or nasal cavity, larynx and trachea which is where air travels down into the lungs. Inside the lungs are the bronchi is where you see the small tree like tubes and at the end of each one are little sacs of air called alveoli. The alveolus moves oxygen into your blood stream and takes carbon dioxide out.
The Digestive System
We all eat. It's a part of living. Most of us know that when we eat we get energy or if we eat too much we get fat. In this unit we are taking a closer look at our digestive system. The digestive system is like the tool our bodies uses to take in food and turn it into different things like fat, energy, and poop. Our digestive system helps us take all the good things we get from fruits and vegetables and use them all over our bodies. Here is a diagram that shows the different steps a piece of food travels through from our mouth to our rectum.