2.  Food gives living things the energy they need to  Live  Grow  Reproduce Chemical energy and food

3.  Our cells can use proteins, fats, or sugars for food  A Calorie (1000 calories) measures the heat energy released when food is digested.  The first step to release the energy in food is glycolysis Lyse: to cut Glyco: sugar

4.  This process releases energy by:  Breaking down glucose and other food molecules in the presence of Oxygen  It turns food into energy in small steps.

5.  A 6-Carbon glucose is broken in half, making two 3-C pyruvic acids  2 ATP are made  2 NADH are made (e - carrier)  Happens in the cytoplasm.  After glycolysis, the pyruvic acid can take 1 of 3 different paths 1 glucose becomes 2 pyruvic acids

6.  When Oxygen is NOT present, the process is called anaerobic.  Type 1:Alcoholic Fermentation:  Pyruvic acid + NADH  alcohol + CO 2 + NAD +  CO 2 gas helps bread to rise when yeast ferments. yeast #1 Fermentation

7.  Pyruvic acid + NADH  lactic acid + NAD +  Happens in muscles during rapid exercise, when they can’t get enough O 2. Causes pain or cramps.  LAF in single celled procaryotes make foods like cheese, yogurt, sour cream, and pickles type 2: Lactic acid fermentation

8. # 3: in the presence of O 2, pyruvic acid moves into a mitochondrion to begin aerobic respiration.