Foothill High School Science Department Cellular Respiration Chemical Pathways

Foothill High School Science Department Chemical Energy & Food Energy 1 gram Glucose = 3811 calories but when is A Calorie Is NOT a calorie

Foothill High School Science Department Chemical Energy & Food calorie ( little c, energy unit ) –Is The Energy Needed To Raise 1g of WaterRaise 1g of Water 1 degree Centigrade1 degree Centigrade Calorie (Capital C) –Food Energy Unit –Equals 1000 calories

Foothill High School Science Department Chemical Energy & Food Cells –Don’t BURN Glucose –They Gradually Release The Energy Stored In Glucose, Through Cellular Respiration Step #1 = Glycolysis

Foothill High School Science Department Glycolysis Key Concept: During Glycolysis, 1.Glucose Is Broken In Half 2.To Produce Two Molecules Of Pyruvic Acid A Three Carbon Compound

Foothill High School Science Department Glycolysis - Cytoplasm Invest Two ATP’s To Make Four ATP’s Net Gain = 2 ATP’s Net Gain = 2 ATP’s

Foothill High School Science Department Glycolysis NAD+ …. Accepts 2 Electrons To Form … NADH NADH = Nicotinamide Adenine Dinucleotide

Foothill High School Science Department Glycolysis The Purpose of Glycolysis is The Production of NADH Look Familiar?

Foothill High School Science Department Overview of Cellular Respiration Key Concept : Cellular Respiration Is The Process That Releases Energy By Breaking Down Glucose Is The Process That Releases Energy By Breaking Down Glucose In The Presence Of Oxygen

Foothill High School Science Department Overview of Cellular Respiration Cellular Respiration Krebs Cycle Electron Transport Chain Following Glycolysis – The Pyruvic Acids Pyruvic AcidsPyruvic Acids Have Two Choices If Oxygen is Present If Oxygen is NOT Present The Pyruvic Acid Is Moved Into The Mitochondria Where The Pyruvic Acid Stays In The Cytoplasm Where Fermentation Alcoholic or Lactic Acid

Foothill High School Science Department Cellular Respiration Cellular Respiration Glycolysis Oxygen Present? Aerobic Respiration Fermentation Yes No Cytoplasm Mitochondria

Foothill High School Science Department Fermentation Anaerobic Pathway = No Oxygen Key Concept : Two Types Of Fermentation: 1.Alcoholic Fermentation 2.Lactic Acid Fermentation

Foothill High School Science Department Fermentation Why Ferment? 1.Frees Up NAD+ 2.Allows Glycolysis To Proceed –At least you get 2 more ATP

Foothill High School Science Department Fermentation Alcoholic FermentationAlcoholic Fermentation –Used By Yeasts & Other Microorganisms –Used To Make Bread, Beer, etc. CO 2 Released As BubblesCO 2 Released As Bubbles Alcohol Bakes OutAlcohol Bakes Out

Foothill High School Science Department Fermentation Alcoholic Fermentation Pyruvic Acid + NADH Alcohol + CO2 + NAD+

Foothill High School Science Department Fermentation Lactic Acid Fermentation Anaerobic Metabolism Of Animal Cells Causes Pain & Fatigue Pyruvic Acid + NADH Lactic Acid + NAD+

Foothill High School Science Department Why Ferment? Fermentation Because If You Can Ferment You Get To LIVE ! Net Gain = 2 ATP’s Net Gain = 2 ATP’s