Molecule made up of a 2-carbon acetyl group attached to coenzyme A. During cellular respiration, the acetyl group enters the citric acid cycle for further breakdown.
citric acid cycle
Cycle of reactions in mitochondria that begins with citric acid. It breaks down an acetyl group and produces CO2, ATP, NADH, and FADH2; also called the Krebs cycle.
coenzyme
Nonprotein organic molecule that aids the action of the enzyme to which it is loosely bound.
coenzyme A (CoA)
Molecule that helps oxidate pyruvate in the preparatory (prep) reaction during cellular respiration.
electron transport chain
Passage of electrons along a series of electron carriers from a higher to lower energy level; the energy released is used for the synthesis of ATP.
fermentation
Anaerobic breakdown of glucose that results in a gain of 2 ATP and end products such as alcohol and lactate.
glycolysis
Anaerobic breakdown of glucose that results in a gain of 2 ATP and the end product pyruvate.
intermembrane space
Space that occurs between the outer and inner membrane of a mitochondrion.
oxygen deficit
Amount of oxygen needed to metabolize lactate, a compound that accumulates during vigorous exercise.
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.