Aerobic Respiration

You gotta love helpful wives. Not only does she drill me with flash cards without complaint, she also had a wonderful suggestion to write a brief summary of what happens during aerobic respiration in order to cement it in my mind. So thats what I did! Wrote completely from memory and as far as I understand the process it's correct. I'm totally going to kick this tests ass.

Aerobic respiration is composed of three stages, Glycolysis, the Citric Acid Cycle, and the Electron Transport Chain.

Glycolysis begins with a six carbon sugar that has two phosphates attached with the expenditure of two ATP (Adenine Triphosphate) leaving you with a six carbon sugar diphosphate and two ADP (Adenine Diphosphate). The six sugar diphosphate is then cleaved into two three-carbon molecules. Those two three-carbon molecules then go through a series of changes. A coenzyme called NAD+ bonds with electrons in the three-carbon molecule creating NADH while creating four ATP and two pyruvic acid molecules. Since we have to "pay back" the ATP that was used at the beginning of this process we are left with a net of two ATP.

The two Pyruvic Acid molecules now expend their ATP to enter into the matrix of the mitochondria expending CO2 and creating more NADH turning into Acedic acid. A CoA is added to the Acedic Acid creating Acetyl CoA which then enters into the actual Citric Acid Cycle, during which four carbon molecules are added to the Acetyl CoA creating Citric Acid. During the cycle the citric acid experiences a series of changes giving off yet more NADH and CO2, as well as one ATP for each Pyruvic acid leaving us with two ATP, NADH, and some CO2 at the end of the Citric Acid Cycle. The CO2 is exhaled and the NADH move on to the third and final stage of Aerobic Respiration; the Electron Transport Chain

The NADH transfers its Hydrogen+ protons and the electrons gathered in the first two processes to a transmembrane protein. The electrons travel through the electron transport chain and the hydrogen protons use the energy from the electrons to move up it's gradient and out into the intramembrane space. The electrons eventually bond with free floating Hydrogen and O2 molecules within the matrix of the mitochondria and form H2O (water), while the Hydrogen protons in the intramembrane space move through the ATP Synthase. The energy created by this process allows molecules of ADP+P to be bound together creating ATP.