Chapter 7 Section 2 I. Aerobic Respiration a. Overview of aerobic 1. Aerobic respiration has two major stages; the Krebs Cycle and the electron transport chain. 2. In the Krebs cycle, the oxidation of glucose that began with glycolysis is completed. 3. In the electron transport chain, NADH is use to make ATP. 4. In prokaryotes the reactions take place in the cytoeol. 5. In eukaryotes the reactions take place in the mitochondria. 6. The mitochondrial matrix is the space inside the inner membrane of the mitochondrion. 7. When pyruvic acid enters the mitochondrial matrix, it reacts with a molecule called coenzyme. b. The Krebs Cycle 1. The Krebs Cycle is a biochemical pathway that breaks down acetyl CoA, producing CO2, hydrogen atoms and ATP. 2. In the first of the Krebs Cycle, a two-carbon molecule of acetyl CoA combines with a four-carbon compound, oxaloacetic acid to produce citric acid. 3. In step 2, Citric acid releases a CO2 molecule and a hydrogen atom to form a five-carbon compound. 4. In step 3, the five carbon molecules release another molecule of CO2 and a hydrogen atom to form a four-carbon molecule. 5. In step 4, the four carbon compound releases a hydrogen atom to form another four-carbon compound. 6. In the last step, the four-carbon compound releases a hydrogen atom to regenerate oxaloacetic acid. c. Electron Transport chain and Chemiosmasis
1. Electron transport chain is a series of molecules in a membrane that transfer electrons from one molecule to another.
2. In eukaryotes, the ETC and ATP synthase are embedded in the inner membrane of the mitochondrion called cristae.
3. In prokaryotes, the ETC is in the cell membrane.
4. In step 1, NADH and FADH2, give up electrons at the beginning.
5. In step 2, the electrons are passed down the chain losing energy moving molecule to molecule.
6. In step 3, the energy lost from the electrons is used to pump protons