Travis Carlton Bio Lab 5 4/29/2018 1a. Cellular respiration is used to produce ATP, which is the cells main source of energy. There are three stages to cellular respiration which are glycolysis, citric acid cycle (Krebs cycle), and oxidative phosphorylation. Aerobic respiration, requires oxygen in the process of making ATP. 1b. Fermentation doesn’t produce ATP itself but does produce NAD+ which is used during glycolysis, which does produce two molecules of ATP. Fermentation is an anaerobic pathway which means it doesn’t require oxygen in its process. 2a. Glycolysis takes place in the cytoplasm of the cell and breaks down one glucose molecule into two molecules of pyruvate at the expense of two ATP molecules. The products of glycolysis are four ATP molecules, two pyruvic acid molecules, and two molecules of NADH from the reduction of NAD+. 2b. The Krebs cycle (citric acid cycle) takes place in the mitochondria of the cell where pyruvic acid from glycolysis diffuses into the mitochondria. Before pyruvic acid can enter the citric acid cycle it must be converted into acetyl CoA. Once acetyl CoA enters the citric acid cycle it starts a series of redox reactions to continue the cellular respiration process to produce energy. One molecule of ATP gets produced along with one molecule of FADH2 and three molecules of NADH …show more content…
Oxidative phosphorylation also takes place in the mitochondria and makes most of the ATP made by cellular respiration. It has two processes which are the electron transport and chemiosmosis. First some electrons from FADH2 and NADH go through a series of redox reactions until finally being accepted by oxygen. The energy released from each of the redox reactions is used to pump hydrogen atoms across the inner membrane of the mitochondria, which is then used in chemiosmosis. During chemiosmosis hydrogen atoms move back into the mitochondria through enzymes called ATP synthase, which results in ADP getting another phosphate group and becoming