Cellular Respiration 6 O2 + C6H12O6 6CO2 + 6H2O + energy Oxygen + Glucose produce Carbon dioxide + Water + energy RESPIRATION - the process that occurs in cells in which cells break down sugar for ENERGY! Occurs in cytoplasm and Mitochondria Who does this? Autotrophs and Heterotrophs

Cell Respiration can take 2 pathways – both start with GLYCOLYSIS! Means “Splitting Glucose” glyco – refers to glucose lysis – to break down Glucose is broken down into 2 molecules called Pyruvate. Happens in the Cytoplasm. Anaerobic which means does NOT require O2 YIELDS: 2 ATP (Pyruvate and NADH) Glycolysis

Krebs Cycle and Electron Transport Chain KREBS CYCLE & ELECTRON TRANSPORT CHAIN Pyruvate travel to the Mitochondria and enter the Krebs Cycle then the Electron Transport Chain Aerobic which means NEEDS O2 YIELDS: 34 ATP, CO2, H20 36 ATP made but 2 used to move into mitochondria

Krebs Cycle Electron Transport (AKA citric acid cycle) Chain (ETC) The 2 pyruvate from glycolysis diffuse into the matrix of the mitochondria. The 2 pyruvate are converted into 2 acetyl-CoA and 2 CO2 are released. Each Acetyl-CoA enters the Krebs Cycle. (2 complete cycles total) YIELD: 8 NADH, 2 FADH2, 2 ATP, 6CO2 Occurs in cristae in mitochondria. Electron acceptors in the chain accept NADH/FADH2 electrons. As electrons pass down molecules to O2 – the O2 combines with H atoms to form H2O and ATP. YIELD: 10 NADH converts to 30 ATP, 2 FADH2 converts to 4 ATP, 6H2O (FADH produces 2 ATP, NADH produces 3 ATP)

ONE glucose produces 36 ATP during respiration! 38 made and 2 lost traveling to mitochondria

What is there if NO OXYGEN? FERMENTATION Anaerobic Happens in cytoplasm, when the cells are deprived of O2 Lactic Acid forms during increased muscle activity! Cramps result from an increased acidity level. Alcohol fermentation occurs in fungi such as yeast and some bacteria to produce ethanol and CO2. Used in bread, wine and beer  

Electron Transport Chain (34 ATP) Glycolysis (2 ATP) No oxygen present (Anaerobic respiration) Oxygen present (Aerobic respiration) Krebs Cycle (2 ATP) Fermentation pathways (0 ATP) 2 types: Alcoholic fermentation Lactic Acid fermentation Electron Transport Chain (34 ATP) 36 ATP TOTAL

Photosynthesis vs. Cellular Respiration Occurs in producers (autotrophs) Reactions take place in chloroplasts Pathway: 1. Light reactions (light dependent) 2. Dark reactions (light independent) Final results: *CO2 and H2O are REACTANTS *Glucose and O2 are PRODUCTS Occurs in ALL organisms (autotrophs and heterotrophs) Reactions take place in cytoplasm and mitochondria Pathway: 1. Glycolysis - cytoplasm 2. Anaerobic (fermentation) or Aerobic (Krebs and ETC) Final results: * No O2: fermentation - 2 ATP *O2: – 38 ATP *Glucose and Oxygen are REACTANTS *H2O and CO2 are PRODUCTS