Respiration breaks down glucose from food into energy using oxygen. It produces ATP, which transports energy throughout the body. Glycolysis is the first step and breaks down glucose without oxygen. The resulting pyruvic acid then enters the Krebs cycle in the mitochondria using oxygen to produce large amounts of ATP, carbon dioxide, and water. If insufficient oxygen is present, pyruvic acid is instead converted to lactic acid, causing muscle fatigue and pain as it builds up.

1. Respiration By Will F.

2. What is Respiration? Respiration is the process which breaks down glucose from food into energy. It is the reason that we need oxygen flowing throughout our bodies.

3. ATP ATP(adenosine triphosphate) is the body's energy carriers. It transports energy to where it is needed in the human body. It consists of the compound ADP(adenosine diphosphate) and the ion phosphate.

4. Glycolysis Glycolysis is the process which ocurrs when glucose comes to a cell, oxygen is not needed for this. It breaks down one glucose molecule into pryuvic acid molecule, and releases a little bit of ATP.

5. If there is enough oxygen... If there is oxygen avialble then the pyruvic acid goes to mitochodrian. Inside the mitochondrian the Krebs cycle, or citric acid cycle, ocurs. The Krebs cycle needs oxygen, and turns the pyruvic acid into lots of ATP and some carbon dioxide and water.

6. If there is not enough oxygen If the pyruvic acid does not go to the mitochondrian then it turns into lactic acid. Lactic acid mostly goes to the bloodsteam to be broken down later, but some stays in the muscle. This can build up and eventually cause one's muscles to stop working. Lactic acid build up is what makes one pant and makes one's muscles ache.

7. Thank You!