Aerobic cellular respiration is the cellular process of using glucose and oxygen to produce energy. This type of cellular respiration is much more efficient than the anaerobic process, since it produces 36 ATP (cellular energy) per cycle instead of just four.
First, glucose enters the cytoplasm, where it is converted to four ATP units, two NADH units, and two Pyruvate molecules. The NADH units go to the ETC and two of the ATP units go to the matrix.
Next, the pyruvate, two ATP units, and oxygen enter the matrix, where they are converted to two ATP units, 8 NADH units, two FADH2 units, and 6 CO2 molecules. The NADH and FADH2 units go to the ETC.
The ETC, or Electron Transport Chain, converts the 10 NADH and two FADH2 units into 34 ATP units and 6 H2O molecules, which, along with the 6 CO2 molecules from the matrix, have to be released.
What is ATP, NADH, and FADH2?
ATP is the "currency" of the cell. It is a form of energy storage that can either be stored up for future use by the cell or used to "pay" for reactions within the cell, like photosynthesis or glycolysis (the breaking down of sugar).
NADH is another form of energy storage. This is an enzyme made from NAD+ (Nicotinamide adenine dinucleotide) and a hydrogen molecule. It stores more energy than ATP and is used to make it.
FADH2 (flavin adenine dinucleotide) is another molecule that stores energy in cells. It donates electrons to the ETC by providing a hydrogen molecule to an oxygen molecule already present.
As you can see, aerobic cellular respiration is much more efficient than anaerobic cellular respiration, and as a result, it is the method our bodies use most of all. Since our cells can get oxygen most of the time, this method is used more than the anaerobic method.