1. Glycolysis and Fermentation Unit 4: Energize Your Life Ch 9-1

2. Glycolysis Glyco = glucose Lyse = break down One molecule of glucose (C 6 H 12 O 6 ) is broken in half This produces 2 molecules of pyruvic acid (a 3-carbon compound)

3. Glycolysis Glycolysis occurs in the cytoplasm. Glycolysis does NOT require oxygen. It is anaerobic!!! Glycolysis also occurs very rapidly. It can produce thousands of ATP molecules in a few milliseconds.

4. Glucose to ATP Glycolysis is a chemical reaction that releases energy from glucose. The initial energy COST of this chemical reaction is 2 ATP molecules. 4 molecules of ATP are produced. Net gain of 2 ATP!!!

5. Electron Carriers in Glycolysis One of the reactions in glycolysis removes 4 high-energy electrons and converts NAD + into NADH. Each NADH carries 2 electrons. NADH transfers the energy to the Electron Transport Chain (ETC). Without NAD +, glycolysis can NOT occur! All of the NAD + molecules are needed to transport electrons.

6. Glycolysis Glucose To the electron transport chain 2 Pyruvic acid

7. Fermentation Fermentation is also anaerobic. Fermentation happens after glycolysis IF the cell does NOT have Oxygen. Fermentation releases energy from food molecules in the absence of oxygen.

8. Fermentation There are 2 main types of fermentation: –Alcoholic Fermentation –Lactic Acid Fermentation Occur in the cytoplasm

9. Alcoholic Fermentation Pyruvic acid + 2NADH  alcohol + CO 2 + 2NAD + Examples: wine and bread (the alcohol evaporates when baked)

10. Lactic Acid Fermentation Pyruvic acid + 2NADH  lactic acid + CO 2 + 2NAD + Examples: milk, yogurt, & muscles

11. Exercise Without oxygen, the body is not able to produce enough ATP. When you perform ANAEROBIC exercise, you are depriving your muscles of oxygen. Your muscles go through LACTIC ACID FERMENTATION! The lactic acid is what makes you sore!!!

12. If the cell has oxygen… Aerobic—process that occurs in the presence of oxygen Pyruvic Acid goes to the mitochondria; fermentation does NOT occur –Kreb’s Cycle –Electron Transport Chain To be continued…