Jang Jun Hwa
200802967
Intermediate English Writing (1)
Tuesday 7-8 period
a five-paragraph process analysis essay
Simple Process, but Great Value
Parents, clean water and education. What do they have in common? They are what most of us just take for granted. In addition, there is one more important thing. Oxygen. We are unable to live a sing day without oxygen, but we do not realize the value of it. We do not even know how our body receives it. So, let's take this opportunity to check out how the human respiratory system works. It is simple.
First, oxygen enters our body through the mouth and the nose. The hairs in our nose catch dust in the air when we take a breath. What is more, the nose warms up the oxygen and makes it moist. If the nose does not work well, cold air comes into and hurts our respiratory organs. Next, the oxygen is supposed to meet voice box. Voice box is kind of a gate to our body. When the oxygen comes in, it opens.
Then the oxygen travels through windpipe, which is like a passage led to the lungs. On the surface of the windpipe, there are downy hairs which are called ciliation. They function to filter out dust particles or impurities. The windpipe is divided into two bronchial tubes. After passing through two bronchi, the oxygen enters the lungs, which hang at the end of the bronchi.
As the nose and windpipe work, a complex process occurs in our lungs. We have two lungs. The lungs are composed of about 0.3 billion of air sacs and each air sac are covered with blood vessel. Between air sacs and blood vessel, the exchange of air takes place. The oxygen gets absorbed into blood. At the same time, the carbon dioxide, which is emitted by the tissues, is released into our lungs. The reason we breathe out is to get ride of the carbon dioxide.
Once the oxygen comes into our body, many processes are required in the following order: nose, voice box, windpipe, bronchial tubes and lungs. It is easy to understand how our respiratory system works. We inhale to get oxygen and exhale to expel carbon dioxide. But, please remember one thing. This simple process makes us live.