Chapter 7 Flashcards
Define Cellular respiration
The process by which energy rich molecules are broken down to produce energy in the form of ATP during which oxygen is utilized and carbon dioxide is produced
Define Aerobic respiration
Form of cellular respiration found in eukaryotes and many prokaryotes in which oxygen is a reactant in the ATP-producing process
Define Anaerobic respiration
The production of ATP in a number of types of prokaryotes using an electron transport chain in which the final electron acceptor is an inorganic molecule rather than oxygen.
Define Oxidation
The partial or full loss of electrons from a substance
Define Oxidized
Substance- the electron donor- from which the electron are lost during oxidation
Define Reduction
The partial or full gain of electrons to a substance
Define Reduced
Substance- the electron acceptor- that gains electrons during reduction
Define Redox reactions
Coupled oxidation- reduction reaction in which electrons are removed from a donor molecule and simultaneously added to an acceptor molecule
Define Nicotinamide adenine dinucleotide (NAD+)
A coenzyme that serves as an electron carrier
Define Glycolysis
Stage of cellular respiration in which sugar such as glucose are partially oxidized and broken down into smaller molecules
Define Substrate-level phosphorylation
An enzyme catalyzed reaction that transfers a phosphate group from a substrate to ADP
Define Pyruvate oxidation (pyruvic acid oxidation)
Stage of cellular respiration in which the three carbon molecule pyruvate is converted into a two- carbon acetyl group that is completely oxidized to carbon dioxide
Define Citric acid cycle
Series of reactions in which acetyl groups are oxidized completely to carbon dioxide and some ATP molecules are synthesized. Also referred to as Krebs cycle and tricarboxylic acid cycle
Define Oxidative phosphorylation
Synthesis of ATP in which ATP synthase uses an H+ gradient built by the electron transport chain as the energy source to make the ATP
Define Electron transport chain
Stage of cellular respiration in which high-energy electrons produced from glycolysis, pyruvate oxidation, and the citric acid cycle are delivered to oxygen by a sequence of electron carriers
Define Chemiosmosis
In oxidative phosphorylation, the process of generating an H+ gradient from free energy released by electron flow through the electron transport chain
Define ATP synthase
A membrane-spanning protein complex that couples the energetically favorable transport of protons across a membrane to the synthesis of ATP
Define Acetyl-coenzyme A (acetyl- CoA), also known as Acetylcholine)
A neurotransmitter that is release by axon terminal at chemical synapses. It has mostly excitatory effects
Define tricarboxylic acid cycle (TCA cycle)
Series of reaction in whicch acetyl groups are oxidized completely to carbon dioxide and some ATP molecules are synthesized. Also referred to as Krebs cycle and tricarbonxylic acid cycle
Krebs cycle
Series of reactions in which acetyl groups are oxidized completely to carbon dioxide and ATP molecules are synthesized. Also referred to as Krebs cycle and tricarboxylic acid cycle
Define Mitochondrial electron transport chain
Series of electron carriers that alternately pick up and release electrons, ultimately transferring them to their final acceptor, oxygen
Define Proton-motive force
Stored energy that contributes to ATP synthesis, as well as the cotransport of substances to and from mitochondria
Define Chemiosmotic hypothesis
Model proposing that mitochondrial electron transfer produces an H+ gradient and that the gradient powers ATP synthesis by ATP synthase
Define Anaerobic respiration
The production of ATP in a number of types of prokaryotes using an electron transport chain in which the final electron acceptor is an inorganic molecule rather than oxygen
Define Fermentation
Process in which electrons carried by NADH are transferred to an organic acceptor molecule rather than to an electron transport chain
Define Lactate fermentation
Reaction in which pyruvate is converted into lactate
Define Alcoholic fermentation
Reaction in which pyruvate is converted into ethyl alcohol and CO2 in a two step series that also converts NADH into NAD+
Define Strict anaerobes
Organism in which fermentation is the only source of ATP
Define Strict aerobes
Cell with an absolute requirement for oxygen to survive, unable to live solely by fermentations
Define Facultative anaerobes
An organism that can live in the presence or absence of oxygen, using oxygen when it is present and living by fermentation under anaerobic conditions
Define Gluconeogenesis
Glucose biosynthesis from intermediates of the glycolysis and citric acid pathways as well as from molecules derived from those pathways. It is the reverse of glycolysis
