the entry compound for the citric acid cycle in cellular respiration, formed from a fragment of pyruvate attached to a coenzyme.
Containing oxygen; referring to an organism, environment, or cellular process that requires oxygen
Lacking oxygen; referring to an organism, environment, or cellular process that lacks oxygen and may be poisoned by it.
A cluster of several membrane proteins found in the mitochondrial crista (and bacterial plasma membrane) that function in chemiosmosis with adjacent electron transport chains, using the energy of a hydrogen ion concentration gradient to make ATP. Provide a port through which hydrogen ions diffuse into the matrix of a mitrochondrion.
A metabolic sequence that breaks fatty acids down to two-carbon fragments that enter the citric acid cycle as acetyl CoA.
The most prevalent and efficient catabolic pathway for the production of ATP, in which oxygen is consumed as a reactant along with the organic fuel.
An energy-coupling mechanism that uses energy stored in the form of a hydrogen ion gradient across a membrane to drive cellular work, such as the synthesis of ATP. Most ATP synthesis in cells occurs by chemiosmosis.
citric acid cycle
A chemical cycle involving eight steps that completes the metabolic breakdown of glucose molecules begun in glycolysis by oxidizing pyruvate to carbon dioxide; occurs within the mitochondrion in eukaryotic cells and in the cytosol of prokaryotes; the second major stage in cellular respiration.
an iron-containing protein, a component of electron transport chains in mitochondria and chloroplasts
electron transport chain
A sequence of electron carrier molecules (membrane proteins) that shuttle electrons during the redox reactions that release energy used to make ATP.
an organism that makes ATP by aerobic respiration if oxygen is present but that switches to fermentation under anaerobic conditions
a catabolic process that makes a limited amount of ATP from glucose without an electron transport chain and that produces a characteristic end product, such as ethyl alcohol or lactic acid
Nicotinamide adenine dinucleotide, a coenzyme present in all cells that helps enzymes transfer electrons during the redox reactions of metabolism
the production of ATP using energy derived from the redox reaction of an electron transport chain
The potential energy stored in the form of an electrochemical gradient, generated by the pumping of hydrogen ions across biological membranes during chemiosmosis.
A chemical reaction involving the transfer of one or more electrons from one reactant to another; also called oxidation-reduction reaction.