Biology 103 Chapter 8

aerobic

phase of cellular respiration that requires oxygen

anaerobic

growing or metabolizing in the absence of oxygen

catabolism

metabolic process that breaks down large molecules into smaller ones; catabolic metabolism

cellular respiration

metabolic reactions that use energy from carbohydrrate, fatty acid, or amino acid breakdown to prodce ATP molecules

chemiosmosis

process by which mitochondria and chloroplasts use the energy of an electron transport chain to create a hydrogen ion gradient that drives ATP formation

citric acid cycle

Cycle of reactions in mitochondria that begins with citric acid. This cycle breaks down an acetyl group and produces CO2, ATP, NADH, and FADH2; also called the Krebs cycle.

cytochrome

Any of several iron-containing protein molecules that are members of the electron transport chain in photosynthesis and cellular respiration.

deamination

The removal of an amino group (-NH2) from an amino acid or other organic compound.

electron transport chain (ETC)

Passage of electrons along a series of membrane-bound electron carrier molecules from a higher to lower energy level; the energy released is used for the synthesis of ATP.

FAD

Flavin adenine dinucleotide; a coenzyme of oxidation-reduction that becomes FADH2 as oxidation of substrates occurs, and then delivers electrons to the electron transport chain in mitochondria during cellular respiration.

fermintation

anaerboic breakdown of glucose that results in a gain of two ATP and end products such as alcohol and lactate

glycolysis

the anaerobic breakdown of glucose that results in a gain of two ATP and the end product pyruvate

metabolic pool

metabolites that are the products of and/or the substrates for key reactions in cells allowing one type of molecule to be change into another type, such as the conversion of carbohydrates to fats

mitochondrion

membrane-bounded organelle in which ATP molecules are produced during the process of cellular respiration

NAD+

coenzyme of oxidation-reductionthat accepts electrons and hydrogen ions to become NADH+H+ as oxidation of substrates occurs. during cellular repiration, NADH carries electrons to the electron transport chain in mitochondria

oxygen debt

amount of oxygen required to oxidize lactic acid produced anaerobically during strenuous muscle activity

preparatory (prep) reaction

Reaction that oxidizes pyruvate with the release of carbon dioxide; results in acetyl CoA and connects glycolysis to the citric acid cycle.

pyruvate

End product of glycolysis; its further fate, involving fermentation or entry into a mitochondrion, depends on oxygen availability

substrate-level ATP synthesis

Process in which ATP is formed by transferring a phosphate from a metabolic substrate to ADP