Circulatory System

Function:
The function of the circulatory system in to move the blood in your body form your heart and back to your heart. The circulatory system also delivers oxygen to your blood cells and removes waste.

Organs:
heart: The heart works hard to push oxygen rich blood throughout your body. Your heart also works to get the oxygen poor blood back to it to got through the lungs for more oxygen.
veins: Your veins carry poor blood back to your heart and lungs for more oxygen so that it can become rich blood.
arteries: Your arteries carry your rich blood throughout your body. They carry the blood to everywhere in your body. 
lungs: When you breathe oxygen goes to your lungs where your blood cells drop of carbon dioxide and get oxygen.

Other systems: 
        Your circulatory system works with every other system because the circulatory system gives blood to every organ in the body. If you did not have your circulatory system nothing would work.  All of your systems need blood because they give your body oxygen and other nutrients.  All of your organs need oxygen and nutrients and your blood transports oxygen and nutrients. All of your organs and organ systems need your circulatory system.
Analogy: 

The circulatory system is like the roads because:

• You can go almost everywhere in the city and your blood goes everywhere through your body.
• They can take you to and away from places
• when you go you are going usually to get something and then you go

Your veins and arteries are like the roads because they take you places and they take you back. Your lungs are like the stores because you get stuff you need there. You, your car or another way of transport are like cells because you go through or you travel with the roads or highways or your veins and arteries.

Structure and Function:
Your lungs main function is to store the oxygen that you breathe so that your blood can get the oxygen. This a very important thing for your body.
1. You having two lungs makes it faster for your blood to switch the oxygen and the carbon dioxide. It makes it so that giving your blood oxygen is way more efficient.
2. Your lungs are not very large but they are able to hold lots of air. This is important because if your lungs were any small er you would have to breathe a lot more and it would be harder for your body to do this.
3.Your lungs are close to your heart which makes it so that when your heart is giving the blood to your lungs it is fast. If your lungs and heart were too far apart from each other they would not be able to give your blood to each other.


Sources:

https://www.brainpop.com/health/bodysystems/heart/

https://www.brainpop.com/health/bodysystems/circulatorysystem/

http://kidshealth.org/en/kids/csmovie.html

http://www.untamedscience.com/biology/human/circulatory-system/