CH 9

Oxidation

Loss of electrons from a substance.

Reduction

Gain of electrons by a substance.

Oxidized species

Molecules that lose electrons in a redox reaction.

Reduced species

Molecules that gain electrons in a redox reaction.

Glycolysis

The breakdown of glucose to pyruvate, occurring in the cytoplasm of all cells.

Fermentation

The metabolic process that regenerates NAD⁺ in the absence of oxygen.

Pyruvate oxidation

Process where pyruvate enters the mitochondria and is converted to acetyl-CoA.

Electron Transport Chain (ETC)

A series of protein complexes located in the inner mitochondrial membrane that transfer electrons.

Acetyl-CoA

A key metabolic intermediate that enters the citric acid cycle.

Chemiosmosis

The movement of hydrogen ions across a membrane to generate ATP.

Anaerobic respiration

Respiration that uses an electron transport chain with a final electron acceptor other than oxygen.

Deamination

The process of removing amino groups from amino acids.

Beta oxidation

The metabolic process of breaking down fatty acids into acetyl-CoA units.

Proton-motive force

The potential energy stored in the form of a proton gradient across a membrane.

NADH

Electron carrier that donates electrons to the electron transport chain.

FADH₂

Another electron carrier that donates electrons to the electron transport chain.

ATP Synthase

Enzyme that produces ATP from ADP and inorganic phosphate through chemiosmosis.

Citric Acid Cycle

A series of chemical reactions used by all aerobic organisms to generate energy.

Methane (in methanogens)

A byproduct generated during anaerobic respiration when CO₂ is used as an electron acceptor.

ATP production collapse

Occurs when pyruvate dehydrogenase is inhibited, halting energy production.

Oxidized NAD+

Forms when NADH transfers electrons during cellular respiration.

Alcohol fermentation

The process where pyruvate is converted to acetaldehyde and then to ethanol.

Lactic acid fermentation

The process where pyruvate is directly reduced to lactate by NADH.