Chem 21.2 ATP
The most common method for generating energy in the cell occurs when __________ is converted to __________.
a)ATP, ADP b)ADP, ATP c)ATP, AMP d)AMP, ATP a)ATP,ADP When ATP is converted to ADP, energy is released.
Where does the energy to regenerate ATP come from?
a)It is a nonrenewable resource. b)from the catabolism of a fuel molecule c)only by oxidative phosphorylation d)only by substrate-level phosphorylation b).. In nearly every living thing on earth, the energy comes from the catabolism of a fuel molecule. In this way, ATP is a direct link between the limited set of exergonic pathways of catabolism and the multitude of endergonic pathways that power living cells.
Explain the difference between substrate-level phosphorylation and oxidative phosphorylation.
a)Substrate-level phosphorylation is used only when there is no oxygen available to the cell. When there is oxygen available, oxidative phophorylation is used instead. b)Substrate-level phosphorylation involves phosphorylation of ATP to form ADP, while oxidative phosphorylation converts ADP to ATP. c)Substrate-level phosphorylation is an indirect process of ATP production that occurs in other parts of the cell from the reactions that break down glucose. Oxidative phosphorylation is the more direct production of ATP during the breakdown of glucose by oxygen. d)Substrate level phosphorylation occurs directly during certain steps of glucose breakdown, while oxidative phosphorylation is a more complicated process that occurs in other parts of the cell and uses an external electron acceptor. d)... ATP is generated through two mechanisms during the breakdown of glucose. A few ATP molecules are generated (that is, regenerated from ADP) as a direct result of the chemical reactions that occur in the catabolic pathways. A phosphate group is removed from an intermediate reactant in the pathway, and the free energy of the reaction is used to add the third phosphate to an available ADP molecule, producing ATP. This very direct method of phosphorylation is called substrate-level phosphorylation. Most of the ATP generated during glucose catabolism, however, is derived from a much more complex process, chemiosmosis, which takes place in mitochondria within a eukaryotic cell or the plasma membrane of a prokaryotic cell. Chemiosmosis, a process of ATP production in cellular metabolism, is used to generate 90 percent of the ATP made during glucose catabolism and is also the method used in the light reactions of photosynthesis to harness the energy of sunlight. The production of ATP using the process of chemiosmosis is called oxidative phosphorylation because of the involvement of an external electron acceptor in the process.
The production of ATP using the process of chemiosmosis is called __________.
a)osmosis b)oxidative phosphorylation c)substrate-level phosphorylation d)dephosphorylation b)... The production of ATP using the process of chemiosmosis is called oxidative phosphorylation because of the involvement of oxygen in the process.
