AP Biology Ch.9 Cellular Respiration (Campbell)

a partial degradation of sugars that occurs without the use of oxygen; a catabolic process
Cellular respiration
the catabolic pathways of aerobic and anaerobic respiration, which break down organic molecules for the production of ATP; but it is also a synonym for aerobic respiration
Aerobic Respiration
a catabolic pathway in which oxygen is consumed as a reactant along with the organic fuel; the most efficient catabolic pathway
the loss of electrons from a substance
the addition of electrons to a substance
Redox reaction
a chemical reaction involving the complete or partial transfer of one or more electrons from one reactant to another; oxidation-reduction reactions
Oxidizing agent
the electron acceptor
a coenzyme that can accept an electron and acts as an electron carrier in the electron transport chain
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
occurs in the cytosol, begins the degradation process by breaking glucose into two molecules of a compound called pyruvate
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
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; electron transport and chemiosmosis; "industrial" way of making ATP
Substrate-level phosphorylation
The formation of ATP by an enzyme directly transferring a phosphate group to ADP from an intermediate substrate in catabolism; occurs during glycolysis and the Krebs cycle
Acetyl CoA
the entry compound for the citric acid cycle in cellular respiration, formed from a fragment of pyruvate attached to a coenzyme
an iron-containing protein that is a component of electron transport chains in the mitochondria and chloroplasts of eukaryotic cells and the plasma membrane of prokaryotic cells
the process in which energy stored in the form of a hydrogen ion gradient across a membrane is used to drive cellular work such as the synthesis of ATP
Proton-motive force
the potential energy stored in the form of an electrochemical gradient, generated by the pumping of hydrogen ions across a biological membrane during chemiosmosis
ATP synthase
A complex of several membrane proteins that provide a port through which protons diffuse. This complex functions in chemiosmosis with adjacent electron transport chains, using the energy of a hydrogen ion concentration gradient to make ATP; found in the inner mitochondrial membrane of eukaryotic cells and the plasma membrane of prokaryotic cells
Obligate anaerobe
An organism that only carries out fermentation or anaerobic respiration; such organisms cannot use oxygen and in fact may be poisoned by it
Facultative anaerobe
an organism that makes ATP by aerobic respiration if oxygen is present but that switches to anaerobic respiration or fermentation if oxygen is not present
Alcohol fermentation
a type of fermentation where the pyruvate is converted to ethanol (ethyl alcohol) in two steps
Lactic acid fermentation
a type of fermentation where the pyruvate is reduced directly by NADH to form lactate as an end product, with no release of CO2
Beta oxidation
a metabolic sequence that breaks the fatty acids down to two-carbon fragments, which enter the citric acid cycle as acetyl CoA
Reducing agent
the electron donor in a redox reactions