Bio Chap 9

When ATP is hydrolyzed into ADP and inorganic phosphate, _____. the energy of the ATP molecule stays the same energy is required a large amount of energy is consumed a large amount of energy is released

Which answer best explains why organisms that have an ETC as well as fermentation pathways almost never ferment pyruvate if the electron acceptor required by the ETC is available? The ETC outcompetes fermentation pathways for use of the electron acceptor. The molecule formed by addition of an electron to pyruvate is toxic to the cell. Fermentation is extremely inefficient in terms of the number of ATP molecules produced for each molecule of glucose metabolized. Fermentation is extremely inefficient because it is so slow.

_____ is the three-carbon sugar that is produced as an end product of glycolysis. Pyruvate Acetyl CoA Fructose ADP

At the end of cellular respiration, protons flow through a protein called _____,.which drives the formation of ATP from ADP and inorganic phosphate. ADP phosphorylase acetyl CoA cytochrome c ATP synthase

Why is ATP production during cellular respiration characterized as indirect? ATP is produced by enzymes indirectly associated with the ETC that perform substrate-level phosphorylation. Most of the ATP is produced during glucose oxidation, which occurs through a series of intermediate steps. ATP is not produced directly by the ETC but instead via the proton gradient generated during electron transport through the ETC. Electrons are not passed directly from NADH and FADH2 to O2 but indirectly through the ETC.

In cellular respiration, glucose is _____ and oxygen is _____. reduced, oxidized phosphorylated, dephosphorylated oxidized, reduced produced, degraded

What purpose does fermentation serve? It regenerates NAD+ from NADH to keep glycolysis going in the absence of oxygen. Under aerobic conditions, it drives the formation of acetyl CoA, which then feeds into the citric acid cycle. It allows for the production of NADH, which keeps the electron transport chain going. It produces an abundance of ATP when oxygen is present.

How do allosteric regulation and competitive inhibition compare? Competitive inhibition involves binding of a regulatory molecule to the active site; in allosteric regulation a regulatory molecule binds to a different location. Allosteric regulation involves binding of a regulatory molecule to the active site; in competitive inhibition a regulatory molecule binds to a different location. Both involve binding of a regulatory molecule to the active site. Both involve binding of a regulatory molecule to a location other than the active site.

Which answer best explains why aerobic respiration produces more ATP per mole of glucose than either anaerobic respiration or fermentation? Among known electron donors, O2 is most electronegative. Among known electron acceptors, pyruvate is most electronegative. Among known electron acceptors, O2 is most electronegative. Among known electron acceptors, O2 is least electronegative.

When one molecule gains an electron from another, the molecule that received the electron has been _____. reduced oxidized destroyed redoxed

What job does the electron transport chain accomplish in order to drive the formation of ATP? Electrons are released from oxygen and given to ATP, which forms ADP and inorganic phosphate. Carbon dioxide is used to produce acetyl CoA, which in turn donates electrons to ADP to drive the formation of ATP. The electron transport chain produces carbon dioxide, which in turn forms ATP. The proteins in the electron transport chain pump protons from the matrix of the mitochondria to the intermembrane space, thus establishing an electrochemical gradient.

What molecule is produced in the citric acid cycle as a by-product of glucose oxidation and is subsequently released into the bloodstream and carried to the lungs, where it is removed from the body? oxygen water carbon dioxide nitrogenous wastes