The Krebs cycle is the sequence of reactions by which most living cells generate energy during the process of aerobic respiration. It is also called the Citric acid cycle. In the cell, the Krebs cycle takes place in the mitochondria. This process starts with acetyl CoA and produces NADH, ATP, and carbon dioxide among others. This is the second stage in the process of cellular respiration. The Krebs cycle tries to generate energy through the oxidation of acetate, which is derived from carbohydrates, fats, and proteins into carbon dioxide. These plants, in the picture, use the Krebs cycle.