Cellular Respiration

The process that releases energy from food in the presence of oxygen Cellular Respiration The process that releases energy from food in the presence of oxygen

Processes that do NOT require oxygen are considered anaerobic Aerobic v. Anaerobic Oxygen is required at the very end of respiration in the electron transport chain. Cellular processes that require oxygen are aerobic Processes that do NOT require oxygen are considered anaerobic The three stages of Cellular respiration are: 1. Glycolysis, 2. The Krebs Cycle, and 3. Electron Transport & ATP Synthesis

Glycolysis 1 molecule of glucose (a 6 carbon compound) is transformed into 2 molecules of pyruvic acid (a 3 carbon compound) ATP Production 2 ATP molecules used to “get things going” 4 ATP molecules produced = gain of 2 ATP molecules NADH Production NAD+ accepts 2 electrons =the 2NADH and holds them until they can be transferred to electron chain Glycolysis does NOT require oxygen Happens in the CYTOPLASM of the cell

FOR EACH PYRUVIC ACID Molecule (there are 2) The Krebs Cycle Pyruvic Acid is broken down into carbon dioxide in a series of energy extracting reactions (AEROBIC) Happens in the MATRIX of the Mitochondria FOR EACH PYRUVIC ACID Molecule (there are 2) Citric acid is broken down is a series of reactions 3 molecules of carbon dioxide 1 ATP, 4 NADH & 1 FADH2 (go to electron transport chain)

Electron Transport Chain & ATP Synthesis  Uses high energy electrons from glycolysis and the Krebs cycle to convert ADP to ATP Electron Transport NADH and FADH2 pass their high energy electrons to the electron transport chain (electron carriers located in the inner membrane of mitochondria) At the end of the chain an enzyme combines electrons with hydrogen ions and oxygen to form water Oxygen is the final electron acceptor and the chain can’t function without it Forms a proton gradient used is ATP production (H+ from the NADH and FADH2) ATP Production ATP synthase located in the inner membrane wall ADP molecules are turned into ATP molecules

Together Glycolysis, the Krebs Cycle, and the Electron Transport chain results in about 36 molecules of ATP per 1 molecule of glucose.

https://www.youtube.com/watch?v=-Gb2EzF_XqA

Electron Transport Chain & ATP synthase Stage Where does it happen Inputs Outputs Glycolysis Krebs Cycle Electron Transport Chain & ATP synthase