Lecture 13.6

• Metabolic pathways capture energy from high-energy molecules.
• Most cells have enough to last 30 seconds.
• Glucose is stored as glycogen (animals) or starch (plants).
• Many redox reactions are involved in the oxidation of glucose.
• Cellular respiration is a set of four processes: glycolysis, transition reaction, krebs cycle, electron transport.
• Cells will first use carbohydrates, then fats, and finally proteins in order to generate ATP.
• Oxygen enters cells via simple diffusion and glucose enters cells through facilitated diffusion.
• Glycolysis takes place in the cytoplasm, starts with one glucose molecule, takes 2 ATP to start, generates 4 ATP when the glucose bond is broken, also produces 2 NADH molecules and 2 pyruvates. This process nets 2 ATP.
• Transition reaction occurs in the Mitochondrial Matrix, starts with 2 pyruvates, produces 2 CO2, 2 NADH, and 2 acetyl CoA, you net with 0 ATP.
• The transition reaction occurs twice for every glucose molecule.
• Krebs cycle takes place in the mitochondrial matrix, you start with 2 acetyl CoA, produces 4 CO2, 2 ATP, 6 NADH, and 2 FADH2. Nets 2 ATP.
• The Krebs cycle turns twice for every glucose molecule.
• The electron transport chain starts in the inner membrane and the cristae of mitochondria. You start with 10 NADH, and 2 FADH2. You produce 32 ATP, and 6 H20. Your net ATP is 32.
• Each molecule of glucose that we start with produces a total of 36 ATP.
• Modern research shows that a cell actually nets 29 ATP.