2 Chemical Energy and Food Living things get the energy they need from food.The process of releasing the energy stored in food is cellular respiration.
3 Overview of Cellular Respiration In the presence of oxygen, aerobic respiration takes place.This produces 36 ATP per molecule of glucose.In the absence of oxygen, anaerobic respiration (fermentation) takes place.This produces 2 ATP per molecule of glucose.
5 GlycolysisBoth aerobic and anaerobic respiration begin with a process known as glycolysis.This means “glucose -splitting”This takes place in the cytoplasm.
6 To the electron transport chain GlycolysisSection 9-1Glucose2 Pyruvic acidTo the electron transport chain
7 To the electron transport chain GlycolysisSection 9-1Glucose2 Pyruvic acidTo the electron transport chain
8 To the electron transport chain GlycolysisSection 9-1Glucose2 Pyruvic acidTo the electron transport chain
9 GlycolysisIf oxygen is available, the pyruvic acid molecules will be broken down further to release more energy.If oxygen is unavailable, the pyruvic acid molecules will be converted to a waste product with no further release of energy (fermentation).
11 Fermentation Also known as anaerobic respiration. Two types: Alcoholic fermentation – in yeastsPyruvic acid is converted to alcohol and carbon dioxide.Lactic acid fermentation – in bacteria and muscle cellsPyruvic acid is converted to lactic acid.
16 Aerobic RespirationIn the presence of oxygen, pyruvic acid is further broken down to release additional energy.This takes place in the mitochondria.There are two steps:The Krebs CycleThe electron transport chain
17 The Krebs Cycle Also known as the citric acid cycle. Pyruvic acid (from glycolysis) is broken down into carbon dioxide.High energy electrons are captured by NAD and FAD and brought to the electron transport chain.Net gain of 2 ATP from this cycle.
18 The Krebs CycleSection 9-2Citric Acid ProductionMitochondrion
19 Electron Transport Chain NADH and FADH2 drop off high energy electrons.These pass through a series of reactions located on the inner membrane that produce ATP.Oxygen combines with hydrogen to make water.Net gain of ATP = 32
20 Electron Transport Chain Section 9-2Electron TransportHydrogen Ion MovementChannelMitochondrionIntermembraneSpaceATP synthaseInnerMembraneMatrixATP Production