Krebs Cycle Overview

•  The Krebs cycle is also called the citric acid cycle or the tricarboxylic acid cycle. This cycle involves a series of chemical reactions required for cellular respiration that includes: redox, dehydration, hydration, and decarboxylation reactions. These reactions produce ATP (adenosine triphosphate), a coenzyme energy carrier for cells. The waste product, in the form of carbon dioxide, is also produced as well as further sets of reactants regenerate the original reaction.
•  The main function of the Krebs cycle is to produce energy and occurs in all cells that use oxygen. When combined with the process of oxidative phosphorylation, the Krebs cycle produces more than 95% of energy for humans.
•  Lipid metabolism is associated with carbohydrate metabolism because products of glucose (such as acetyl CoA) can be converted into lipids.
•  Energy from fat is obtained by breaking down triglycerides through hydrolysis into their two principal components, fatty acids and glycerol. This process called lipolysis is centered in the cytoplasm. The fatty acids are oxidized by β-oxidation into acetyl CoA, which is used by the Krebs cycle.
•  Fat molecules produce more energy than carbohydrates, and triglycerides yield more than twice the amount of energy when compared to carbohydrates and proteins. Therefore, when glucose levels are low, triglycerides can be converted into acetyl CoA molecules in the Krebs cycle and used to generate ATP through aerobic respiration.
•  Anaerobic activities such as weight lifting and sprinting do not require the body to utilize the Krebs cycle for obtaining energy. However, activities like long distance running or extended cardio need the aerobic metabolic pathway of the Krebs cycle for energy production.
• The Krebs cycle is the only metabolic pathway that will burn fat along with carbs and protein for energy production, and this cycle is the only real way that fat is used as an energy source.