Why+do+humans+need+to+breathe?+Part+1

__ Breathing and other Facts __

__ By ____ Thuc D 2011 __

__ Why Do we need to Breath? __ In our body, there are cells and these cells need oxygen to live. Our cells also produce a waste which is called carbon dioxide, a toxic to our body. A breathing process called respiration help to provide oxygen to the cells and release carbon dioxide out of our body.

__ How do we Breathe? __ The respiratory system consists of a nasal cavity, throat (pharynx), voice box (larynx), wind pipe (trachea), bronchi, and lungs.

There is a diaphragm in your stomach that bends downward when you inhale oxygen. When you exhale, your diaphragm bends upward, causing pressure so air is not able to get in your lungs (look at diagram below). Think of it like a trade, you trade carbon dioxide for oxygen. The exchange or trade of these gases is called cellular respiration. The respiratory system is responsible for getting air from the atmosphere to your lungs. Then the lungs transfer oxygen to your blood which transports it to your cells. At the same time, the blood circulation removes carbon dioxide building up in your cells and transports it back to your lungs. You then exhale out the carbon dioxide.



__ What is Oxygen? __  What do you think is the most important: water, food, or oxygen? The most important one is oxygen. Because without oxygen then you could die in about 3 minutes, except a pearl diver, who could last up to 6 minutes. But without water, you could survive for several days and without food, you could survive for several weeks. Oxygen is a colorless, odorless, and tasteless gas that is essential to all living things. The most abundant element is oxygen (chemical symbol O). It is one of the main elements in the air around us. We are made up of about 2/3 of oxygen. Oxygen is a very active chemical, combining with nearly all elements. Most of all plants and animals need oxygen for respiration. At under minus 189 Celsius, it is a pale blue liquid, but under minus 218 Celsius, it turns into a solid. There are 3 natural atomic forms (isotopes of oxygen.) The lightest and most abundant one is oxygen-16. There is also oxygen-17 and oxygen-18.

__ What is Carbon Dioxide? __ Carbon dioxide is a colorless gas with a sharp odor and sour taste. Carbon dioxide has 1 molecule of carbon and 2 molecules of oxygen (CO2). Carbon dioxide is bad for you because it will diminish the efficiency of the function of your brain. After a while, your brain will stop functioning or you will suffocate. Green plants make nutrients out of it. Carbon dioxide is formed when carbon-containing material like wood is burnt with a lot of oxygen. When carbon dioxide is dissolved into water, it forms carbonic acid. When this weak acid reacts to some substances, it forms carbonates. One kind of important carbonate is one called sodium bicarbonate or baking soda. Like in biscuits, this occurs in baking powder or between baking soda and sour milk. That is what makes the dough rise. Another example is a sprite can. When it is tightly closed, there is high air pressure. When you open it, the gas bubbles out and create a hissing noise (look at diagram below).



__ Conclusion __ Without breathing, we would only survive for about 3 minutes. Oxygen is one of the nutrients for our cells. Lungs, diaphragm, and blood circulation help our cells to perform an exchange of oxygen and carbon dioxide. The answer for why do we need to breathe is because our cells need oxygen to survive.

__ Glossary __
 * Bronchi- ** either of the two main branches of the trachea that leads directly to the lungs
 * Carbonate- ** a salt
 * Carbonic Acid- ** a weak acid that forms when carbon dioxide is dissolved in water
 * Diaphragm- ** a muscle that separates two cavities and also helps the lungs to work
 * Isotope- ** one of two or more atoms having the same atomic number but different mass numbers
 * Larynx- ** voice box
 * Nasal Cavity- ** is a large air filled space above and behind the nose, in the middle of the face
 * Pharynx- ** throat
 * Respiration- ** inhalation and exhalation of air
 * Sodium Bicarbonate- ** baking soda
 * Trachea- ** windpipe

__ Citations __ Citation (MLA) Breathing. Prod. Cochran. Cochran, 1992. Discovery Education. Web. 15 September 2011. . Citation (APA) Cochran (Producer). (1992). Breathing. [Video Segment]. Available from http://www.discoveryeducation.com/ Citation (Chicago Manual of Style) Cochran. Breathing. From Discovery Education. Video Segment. 1992. http://www.discoveryeducation.com/ (accessed 15 September 2011). carbon dioxide." Compton's by Britannica. Encyclopædia Britannica Online School Edition. Encyclopædia Britannica, Inc., 2011. Web. 15 Sept. 2011.  . carbon dioxide. (2011). In Compton's by Britannica. Retrieved from http://school.eb.com/all/comptons/article-9273513 Encyclopædia Britannica Online School Edition, s.v. "carbon dioxide," accessed September 15, 2011, http://school.eb.com/all/comptons/article-9273513. carbon dioxide 2011. Encyclopædia Britannica Online School Edition. Retrieved 15 September 2011, from http://school.eb.com/all/comptons/article-9273513oxygen." Compton's by Britannica. Encyclopædia Britannica Online School Edition. Encyclopædia Britannica, Inc., 2011. Web. 15 Sept. 2011. . oxygen. (2011). In Encyclopædia Britannica. Retrieved from http://school.eb.com/eb/article-279405 Encyclopædia Britannica Online School Edition, s.v. "oxygen," accessed September 15, 2011, http://school.eb.com/eb/article-279405. oxygen 2011. Encyclopædia Britannica Online School Edition. Retrieved 15 September 2011, from [] Roca, Nuria and Marta Serrrano. The respiratory system. New York: Chelsea House publishers, 1995. Print.