How are pyruvate molecules broken down into carbon dioxide?
During respiration, carbohydrates and oxygen are consumed by a plant to produce carbon dioxide, water, and energy. Throughout the first two stages of respiration, the carbohydrate glucose is broken down into carbon dioxide. In the first stage, called glycolysis, each six-carbon glucose molecule is split into two three-carbon molecules of pyruvate. In the Krebs cycle, the second stage, the three-carbon pyruvate molecules are broken down into two smaller acetyl groups. These acetyl groups enter the Krebs cycle where they are oxidized to yield two molecules of carbon dioxide.
