1. Cellular level
1.1. Aerobic respiration (Oxygen is involved)
1.1.1. Glycosis (cytoplasm)
1.1.1.1. Oxidized and 2 molecules of each of the following are formed
1.1.1.1.1. Pyruvic acid
1.1.1.1.2. ATP
1.1.1.1.3. NADH2
1.1.1.1.4. Water
1.1.2. Tricarboxylic acid cycle (mitochondria)
1.1.2.1. Acetyl part of acetyl-CoA is completely oxidized
1.1.2.1.1. Following molecules are derived
1.1.3. Electron transfer chain reaction
1.1.3.1. Molecules of NADH2 & FADH2 (participates)
1.1.3.1.1. 3 molecules of ATP are obtained from each NADH2 molecule (even water molecules are formed)
1.1.3.1.2. 2 molecules of ATP are obtained from each FADH2 molecule (even water molecules are formed)
1.2. Anaerobic respiration (Oxygen is not involved)
1.2.1. Glycolysis
1.2.2. Fermentation
1.2.2.1. Pyruvic acid produces through glycolysis
1.2.2.1.1. Organic acid (converted)
1.2.2.1.2. Alcohol (converted)