Explain the process of cellular respiration. (Excluding ETC)

1: Glycolysis ("splitting of sugar"): This step happens in the cytoplasm.

One Glucose (C6H12O6) is broken down to 2 molecules of pyruvic acid. Results in the production of 2 ATPs for every glucose.

2: Linked Reaction: Pyruvic Acid is shuttled into the mitochondria, where it is converted to a molecule of Acetyl CoA for further breakdown. Acetyl CoA is a two carbon molecule.

3: The Krebs Cycle, or Citric Acid Cycle: Occurs in the mitochondrial matrix.

Acetyl CoA and Oxaloacetate bind together to become citrate. This 6 Carbon molecule under goes Oxidative Decarboxylation twice, the Substrate level ATP formation, then two oxidations to form 2 ATP, 2 FAHD2, 4 CO2, and 6 NADH+H+

4. The Electron Transport Chain: occurs a long the inner membrane of the mitochondria

The hydrogen carriers NADH+H+ and FADH2 provide electrons to the electron transport chain on the inner mitochondrial membrane and push hydrogen protons outside the inner mitochondrial membrane to a level of high concentration
As the electrons cycle through the chain they lose energy, which is used to translocate H+ ions to the intermembrane space (creating a more concentrated gradient)
The hydrogen ions return to the matrix through the transporting enzyme ATP synthase, producing multiple ATP molecules in a process called chemiosmosis
Oxygen acts as a final electron acceptor for the electron transport chain, allowing further electrons to enter the chain
Oxygen combines the electrons with H+ ions to form water molecules
The electron transport chain produces the majority of the ATP molecules produced via aerobic respiration (~32 out of 36 ATP molecules per molecule of glucose)