Chapter 9 Life the Science of Biology

Glycolysis

first step in releasing the energy of glucose, in which a molecule of glucose is broken into two molecules of pyruvic acid

Pyruvate

Organic compound with a backbone of three carbon atoms. Two molecules form as end products of glycolysis

Anaerobic

Process that does not require oxygen

cellular respiration

Process that releases energy by breaking down glucose and other food molecules in the presence of oxygen

Fermentation

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.

oxidation-reduction reaction

a reaction that involves the transfer of electrons between reactants

reduction

gaining electrons

Oxidation

loss of electrons

citric acid cycle

Completes the breakdown of glucose by oxidizing a derivative of pyruvate to carbon dioxide in the mitochondrial matrix

Acetyl CoA

Acetyl coenzyme A; the entry compound for the citric acid cycle in cellular respiration, formed from a fragment of pyruvate attached to a coenzyme.

substrate-level phosphorylation

The enzyme-catalyzed formation of ATP by direct transfer of a phosphate group to ADP from an intermediate substrate in catabolism.

oxidative phosphorylation

The production of ATP using energy derived from the redox reactions of an electron transport chain; the third major stage of cellular respiration.

respiratory chain

a series of membrane associated electron carriers

ATP synthase

Large protein that uses energy from H+ ions to bind ADP and a phosphate group together to produce ATP

proton-motive force

The potential energy stored in the form of a proton electrochemical gradient, generated by the pumping of hydrogen ions (H+) across a biological membrane during chemiosmosis.

Chemiosmosis

A process for synthesizing ATP using the energy of an electrochemical gradient and the ATP synthase enzyme.

alcoholic fermentation

anaerobic process in which cells convert pyruvic acid into carbon dioxide and ethyl alcohol; carried out by many bacteria and fungi such as yeasts

lactic acid fermentation

The conversion of pyruvate to lactate with no release of carbon dioxide.

glucogenesis

formation of glucose

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.