Cellular EnergyEnergy (from breaking down food) is trapped temporarily in ATP Oxygen makes production of ATP more efficientAerobic (aero = with air) reaction ATP is produced in the presence of oxygenSometimes ATP can be produced without oxygenAnaerobic (an = not or non, aero = with air) reaction ATP is produced WITHOUT the presence of oxygen
Cellular RespirationThe two stages of cellular respiration are: 1. Glycolysis- Glucose (simple sugar) is broken down into 2 pyruvates and small amount ATP and NADH2. Krebs Cycle- Pyruvate & NADH are used to make more ATP. Electrons are donated to make an even more ATP
C6H12O6 + 6O2 6CO2+ 6H20 + 38ATP
Glycolysis Breaking Down GlucoseGlycolysis [glyco=carbohydrate (sugar), -lysis=to break)1st stage of cellular respirationAnaerobic processEnzymes in mouths and stomachs break large carbohydrates (ex. Starch) into glucoseGlucose is used in the cytoplasm to fuel Glycolysis
GlycolysisOccurs in the cytoplasm of cellsGlucose is converted into pyruvate producing a small amount of ATP.(Remember glucose is an energy source.)If there is not enough glucose for glycolysis, then lipids can be used. (ex. fats = energy storage) This is what happens when we diet.
Cellular Respiration Under Aerobic ConditionsAerobic RespirationKrebs Cycle:Occurs in mitochondria -Pyruvate produced by glycolysis enters a mitochondria & gets converted to Acetyl-CoA-Acetyl-CoA starts Krebs cycle to produce ATP & NADH.
Cellular Respiration Under Anaerobic ConditionsIf oxygen is not available for respiration, fermentation occursFermentation- recycling of energy (as NAD+) without the presence of oxygenKrebs cycle cant happenTwo types of Fermentation:Lactic AcidAlcohol
Fermentation: Lactic AcidLactic Acid FermentationDuring glycolysis pyruvate is converted to Lactic Acid instead of Acetyl-CoAThis lactic acid can build up in muscle cells causing muscle soreness
Fermentation: Alcohol FermentationAlcoholic FermentationDuring glycolysis pyruvate is converted to ethanol (alcohol)Yeast releases ethanol and carbon dioxide as waste during fermentationThe carbon dioxide causes bread to rise and carbonation of beerEthanol causes the intoxicating effects of alcoholic beverages.
Electron Transport Chain: ReviewDuring AEROBIC respiration energy donated by the Krebs cycle fuels the electron transport chain (ETC)For a small amount of energy put into the chain, the ETC produces a massive amount of ATP.
Cellular Respiration Wrap-Up
Photosynthesis vs. RespirationThe products for photosynthesis are the materials for cellular respiration and visa versaPhotosynthesis starts of with carbon dioxide, water and energy and ends with the production of sugar and waterCellular respiration starts of with sugar and oxygen and ends with the production of carbon dioxide, water and energy.Is storedIs Harvested