Yun Jeong Lee/ Human Respiratory System/ Tuesday 11a.m.

<How does the human respiratory system work?>

 

             201002551 EIT

Yun Jeong Lee

 

             Many people wrongfully think that respiration is simply 'breathing in and out'. However, respiration is the process of converting glucose into energy. It is much more complicated than breathing, because it requires much process and it goes on in every cell in the human body. Human respiratory system includes three major steps.

             First, a person inhales air to allow gaseous exchange between oxygen and carbon dioxide in the lungs. Inhaled air contains lots of oxygen. The oxygen diffuses into hemoglobin in the blood, the oxygen carrying agent, in exchange for carbon dioxide. These oxygen carrying hemoglobin, or oxyhemoglobin, travel through blood vessels until they reach target cells.

             Next, oxygen containing hemoglobin releases oxygen when it reached the body cells. Since there is less oxygen in the cells than in oxyhemoglobin, oxygen diffuses into the body cells due to concentration difference. At the same time, carbon dioxide diffuses out of the cells and into the blood, down the concentration gradient. Then, it is carried back to the lungs for gaseous exchange.

             Finally, oxygen in body cells is used to convert glucose into energy. Oxygen and glucose react to produce carbon dioxide, water, and energy. Energy is used by humans while the side products, carbon dioxide and water, are disposed. Carbon dioxide is exhaled in gas form, and water is released as steam of breath.

             Though human respiration requires breathing in and out, they are not the same. Respiration is a complicated system of gaseous exchange and chemical reactions to produce the energy humans need in order to survive.