Cellular Respiration Respiration • Respiration – the biochemical process that makes ATP from glucose • Occurs in both AND autotrophs and heterotrophs. Respiration • There are two types of respiration, AEROBIC and ANAEROBIC. • Aerobic respiration requires OXYGEN to release energy. • The chemical equation for aerobic respiration is: C6H1206 + 6O2 6H2O + 6CO2 + 36 ATP Glucose Oxygen Water Carbon Dioxide Energy Respiration • Anaerobic respiration DOES NOT REQUIRE OXYGEN. (Also called FERMENTATION) • Both aerobic and anaerobic respiration begin with the same process, glycolysis. Glycolysis • Occurs in CYTOPLASM • Means “split the sugar,” • The chemical equation for glycolysis is: C6H12O6 + 2 ATP 2 Pyruvic acid + 4 ATP Glycolysis 1. Glucose molecules are broken down into 2 pyruvic acid (pyruvate) molecules 2. Two ATP molecules are used and four ATP molecules are created resulting in a net gain of two ATP. 3. Following glycolysis, the pyruvic acid molecules can follow two paths: aerobic respiration or anaerobic respiration. Glycolysis 2 Glucose Glycolysis Aerobic Respiration • Occurs in the MITOCHONDRIA 1. Pyruvic acid molecules are converted to Acetyl-CoA molecules. 2. Acetyl-CoA broken down into H+, CO2, and ATP • Krebs Cycle 3. The H+ ions bond to carrier molecules, NAD+ and FAD to make NADH and FADH2. Aerobic Respiration 4. NADH and FADH2 go through a series of step reactions – the electron transport chain – to produce ATP. Aerobic Respiration • Each cycle produces 10 NADH molecules, 2 FADH2 molecules and 2 ATP. 1 NADH = 3 ATP 1 FADH2 = 2 ATP • The end product of aerobic respiration is the production of 36 ATP MOLECULES. Aerobic Respiration Glucose 2 36 Glucose Glycolysis Glycolysis Krebs Electron cycle transport Anaerobic Respiration • Occurs in the CYTOPLASM. • Occurs in the absence of oxygen Anaerobic Respiration • Lactic acid Fermentation- converts pyruvic acid to lactic acid and CO2 – Lactic acid can build up in muscles when they run out of oxygen and causes muscle soreness • Alcoholic fermentation- converts pyruvic acid to ethanol and CO2 – Process used to make wine, beer, cheese, and bread • Both processes result in the production of only 2 ATP MOLECULES. Factors Affecting Respiration: • ATP concentration - the more ATP molecules available, the slower the rate of respiration. Anaerobic Respiration 2 36 Glucose Glycolysis Krebs Electron cycle transport Fermentation Alcohol or (without oxygen) lactic acid .