Term | Definition |
cellular respiration | the process by which cells produce energy from carbohydrates; atmospheric oxygen combines with glucose to form water and carbon dioxide |
pyruvic acid | the three-carbon compound that is produced during glycolysis and needed for both the aerobic and anaerobic pathways of cellular respiration that follow glycolysis |
NADH | the reduced form of NAD+; an electron-carrying molecule that functions in cellular respiration |
anaerobic | describes a process that does not require oxygen |
aerobic respiration | if oxygen is present in the cell's environment, pyruvic acid is broken down and NADH is used to make a large amount of ATP through the process |
glycolysis | the anaerobic breakdown of glucose pyruvic acid, which makes a small amount of energy available to cells in the form of ATP |
NAD+ | nicotinamide adenine dinucleotide, an organic molecule that serves as an electron carrier by being oxidized to NAD+ and reduced to NADH |
fermentation | the breakdown of carbohydrates by enzymes, bacteria, yeasts, or mold in the absence of oxygen |
lactic acid fermentation | the chemical breakdown of carbohydrates that produces lactic acid as the main end product |
alcoholic fermentation | the anaerobic process by which yeasts and other microorganisms break down sugars to form carbon dioxide and ethanol |
kilocalorie | a unit of energy equal to 1,000 cal |
mitochondrial matrix | the fluid that is inside the inner membrane of a mitochondrion |
acetyl CoA | acetyl coenzyme A, a compound that is synthesized by cells and that plays a major role in metabolism |
Krebs Cycle | a series of biochemical reactions that convert pyruvic acid into carbon dioxide and water; it is the major pathway of oxidation in animal, bacterial, and plant cells, and it releases energy |
oxaloacetic acid | a four-carbon compound of Krebs cycle that combines with acetyl CoA to form citric acid |
citric acid | a six-carbon compound formed in the Krebs cycle |
FAD | flavin adenine dinucleotide, a compound that acts as a hydrogen acceptor in dehydrogenation reactions |