Grade 12 biology - Cellular Respiration

Aerobic cellular respiration

A process that uses oxygen to harvest energy from organic compounds

Obligate aerobe

an organism that cannot live without oxygen

substrate-level phosphorylation

the formation of ATP by the direct transfer of a phosphate group from a substrate to ADP

Oxidative phosphorylation

a process that forms ATP using energy transferred indirectly from a series of redox reactions

Glycolysis

a series of reactions in which a glucose molecule is broken into two pyruvate molecules and energy is released

Pyruvate oxidation

A reaction in which pyruvate is oxidized by NAD⁺ and C0₂ is removed, forming an acetyl group and releasing NADH

citric acid cycle

a cyclic series of reactions that transfers energy from organic molecules to ATP, NADH, and FADH₂ and releases carbon atoms as C0₂

anaerobic respiration

a process that uses a final inorganic oxidizing agent other than oxygen to produce energy

Fermentation

a process that uses an organic compound as the final oxidizing agent to produce energy

obligate anaerobe

an organism that cannot survive the presence of oxygen

facultative anaerobe

an organism that can live with or without oxygen

decarboxylation reaction

a chemical reaction that removes a carboxyl group to form C0₂

dehydrogenation

the removal of a hydrogen atom from a molecule

protein gradient

a difference in proton concentration across a membrane

proton-motive force

a force that moves protons because of a chemical gradient (often referred to as an electrochemical gradient) of protons across a membrane

chemiosmosis

a process in which ATP is synthesized using the energy of an electrochemical gradient and the ATP synthase enzyme

metabolic rate

the amount of energy that is expended per unit time in an organism

Basal metabolic rate (BMR)

The metabolic rate of an organism at rest

beta-oxidation

A process in which fatty acids are broken down into acetyl-CoA through catabolism

Alcohol fermentation

a process in which pyruvate is decarboxylated, producing a molecule of each C0 and of ethanol, and an NAD⁺

Lactate fermentation

a process in which pyruvate reacts with NADH and is converted directly into lactate and regenerates NAD⁺