Respiratory System

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Respiratory System
Function: provides oxygen for your body and brings oxygen in and out of you body eliminating carbon dioxide,it works with the circulatory system.

Organs: 
Mouth: The mouth is one way your can breathe in air to go to the lungs.
Nose: The nose is also another example of something that you can breathe in and the air will go into the lungs.
Trachea/Wind Pipe: Your wind pipe also called the trachea creates mucus in your nose that prevents unwanted particles and fragments to get to your lungs and inside your body.
Lungs: The lungs is where the air is stored and held on to. Then red blood cells come to collect the oxygen to spread to the body. The lungs also help us get rid of the CO2 gases.
Pharynx: The pharynx allows the air you breath in to go to the lungs. So its technically a passage way the air takes to get from your mouth or nose to the lungs. The Pharynx is also a source for vocals. 

Interaction With Other Systems: The Respiratory System works with the Circulatory System. This is because when the bloods cells pass through the lungs they collect the oxygen so the red bloods cells can distribute it throughout the body. Another system the Respiratory System works with is the Digestive System because your mouth and Pharynx are used for eating and swallowing your food. Last but not least the Respiratory System contributes with the Nervous System because the Nervous System lets us open our mouths to eat and chew it also lets us smell with our nose.

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Analogy: My analogy is a tree because a leaf on the tree acts as a mini lung because the leaf absorbs the oxygen and tosses the carbon dioxide away. The branches represent the bronchi that extends away like the bronchi with the voice box. The tree trunk resembles the  tree trunk because the tree trunk holds the tree up just like the trachea maintains the Respiratory System. The voice box would be the roots because the roots are connected to the trunk while the voice box is connected to the trachea.
Structure And Function: The trachea is a similar to the esophagus is design as a tube so that it can create mucus to catch and prevent any small things from going into you Respiratory System.The way the trachea is medium size is good so that air can flow through smoothly. The areas around the trachea also have mucus which obtains small debris from going into your System while at the same time preventing it from getting into your lungs. A sturdy bone always helps and in this case the bone hold the trachea up and prevents it from falling over.
Sources:
http://science.nationalgeographic.com/science/health-and-human-body/human-body/lungs-article.html
http://kidshealth.org/en/kids/lungs.html
http://kidshealth.org/en/kids/rsmovie.html
http://www.biology4kids.com/files/systems_respiratory.html