In Stage 2 (Krebs Cycle) a carbon dioxide molecule is removed from the
pyruvate along with H+ ions. An acetyl group
This acetyl group is added to a four carbon compound present in the mitochondrion
this produces Citric acid (6C). Citric acid is then broken down in a number
of stages back to the original four carbon compound releasing 2 CO2
molecules, 2 ATP molecules, and numerous
CO2 is released as a waste product and the H+
ion is added to NAD with an electron to form
The NADH releases the electron down a series
of receptors called the electron carrier chain. As the electrons move
down these carriers they release energy which is used to make ATP
from ADP and .
Finally the electrons the H+ ions and oxygen
are combined to form water.