Chemical Energy and Food calorie- the amount of energy needed to raise the temp of 1 gram of water 1 degree Celsius Glucose – releases 3811 calories Food Labels = Calorie (capital C) is 1 kilocalorie – 1000 calories

Cellular Respiration The process that releases energy by breaking down glucose and other food molecules in the presence of oxygen 6O₂ + C₆H₁₂O₆  6CO₂ + 6H₂O + energy 3 main stages – Glycolysis – Krebs Cycle – Electron Transport Chain

Glycolysis Process in which one molecule of glucose is broken in half, producing two molecules of pyruvic acid, and a 3 carbon compound 2 ATP used 4 ATP made Net Gain= 2NAD+ = 2NADH – Accepts 2 e⁻

Fermentation Lack of oxygen Release energy from food molecules by producing ATP Anaerobic- without oxygen Alcoholic Fermentation Lactic acid Fermentation

Alcoholic Fermentation Yeast Pyruvic acid + NADH  alcohol + CO₂ + NAD⁺ - Allows bread to rise

Lactic Acid Fermentation Pyruvic acid + NADH  lactic acid + NAD⁺ Lactic acid- produced by muscles in exercise - cheese, yogurt, buttermilk, sauerkraut, pickles, sour cream