90% if the released energy during the Krebs Cycle comes from what
To determine where 90% of the released energy during the Krebs Cycle comes from, we first need to understand the process. The Krebs Cycle, also known as the Citric Acid Cycle or Tricarboxylic Acid (TCA) Cycle, is a series of chemical reactions that occur in the mitochondria of cells.
During the Krebs Cycle, acetyl-CoA (which is derived from the breakdown of glucose, fatty acids, or amino acids) enters the cycle and undergoes a series of reactions. These reactions result in the production of energy-rich molecules like NADH and FADH2, which carry high-energy electrons.
The energy released during the Krebs Cycle mainly comes from the oxidation of these energy-rich molecules. Specifically, NADH and FADH2 donate high-energy electrons to the electron transport chain (ETC) located in the inner mitochondrial membrane.
The ETC consists of a series of protein complexes that facilitate the transfer of electrons in a stepwise manner. As electrons pass through the ETC, their energy is gradually released and used to pump protons (H+) from the mitochondrial matrix to the intermembrane space, creating an electrochemical gradient.
The electrochemical gradient generated by the ETC is eventually utilized by ATP synthase, an enzyme that synthesizes ATP (adenosine triphosphate) from ADP (adenosine diphosphate) and inorganic phosphate. This process is known as oxidative phosphorylation.
Based on this information, we can conclude that the 90% of released energy during the Krebs Cycle comes from the oxidation of NADH and FADH2 in the electron transport chain, leading to the production of ATP through oxidative phosphorylation.