Presentation on theme: "Chapter 7 pgs Food to energy"— Presentation transcript:
1 Chapter 7 pgs 131-147 Food to energy Cellular RespirationChapter 7 pgsFood to energy
2 Harvesting Chemical Energy From photosynthesis we get carbohydrates (glucose)Cellular respiration: Breaking down the carbohydrates (glucose) to make ATP and NADHNADH is an electron carrierStarts with glycolysisGlyco = sugarLysis = breakingBreaking down sugars
3 What happens after Glycolysis? Chemicals can take one of two pathwaysAnaerobic (no oxygen present) fermentationMakes no ATP, but keeps the cycles goingAerobic respirationMakes a lot of ATP
4 Glycolysis1 six carbon glucose broken down into 2 three carbon pyruvic acid moleculesHappens out in the cytoplasm
5 What happens next depends on whether there is oxygen present or not.
6 FermentationIf there is no oxygen some cells can convert pyruvic acid into other compounds and get some more NAD+No ATP is made, but the NAD+ can keep Glycolysis going to make a little ATP2 kinds of fermentation: Lactic acid fermentation and Alcoholic Fermentation
7 Lactic Acid Fermentation Converting pyruvic acid to Lactic acidA.K.A. milk acidBacteria are used to do this to get cheese, yogurt, and sour creamUnder heavy exercise you use up Oxygen faster than you can replace itLactic Acid builds up and the acidity causes fatigue, pain and cramps.
8 Alcoholic Fermentation Yeast convert pyruvic acid into ethyl alcoholThey break a CO2 off of pyruvic acidThe 2 carbon sugar left behind forms ethyl alcoholBasis of wine and beer industry, and bread making
9 Efficiency of Glycolysis Compare the kilocalories of Glucose with the kilocalories in the ATP that is made.The 2 ATP molecules made during glycolysis receive only 2% of the energy in glucoseWhere does the rest go?It’s still in pyruvic acidThis small amount of energy is enough for bacteria, but more complex organisms need more of glucoses energy.
10 Objectives Define Cellular respiration Describe the major events in glycolysisCompare and contrast lactic acid fermentation and alcoholic fermentationCalculate the efficiency of glycolysis