chapter 7 launchpad
in eukaryotes, pyruvate oxidation takes place in the
mitochondrial matrix
during the citric acid cycle, the production of CO2 is the result of the ______ of intermediate compounds of the citric acid cycle coupled to the production of______
oxidation; NADH
in cellular respiration, glucose is ________ to CO2 and oxygen is ________ to water
oxidized, reduced
the final electron acceptor of the electron transport chain is
oxygen
during cellular respiration, what is reduced and what is oxidized
oxygen;glucose
tracing the metabolism of one glucose molecule, how many carbon atoms are fully oxidized to CO2 at the completion of aerobic respiration
6
the first phase of glycolysis requires the input of two ATP molecules. it is therefore:
endergonic
the immediate source of electrons for the electron transport chain is:
NADH and FADH2
in the cleavage phase of glycolysis
a phosphorylated sugar molecule is broken apart and the products rearranged
true or false: pyruvate oxidation produces a large amount of ATP through substrate-level phosphorylation
false
true or false: fermentation occurs only in anaerobic conditions
false
in which organisms would you expect ethanol fermentation to occur
fungi and plants
excess glucose is stored in large branched molecules of
glycogen in animals
during which phase of glycolysis do we observe pyruvate production, ATP synthesis, and reduction of NAD+
payoff phase
acetyl-coA synthesis occurs during
pyruvate oxidation
in pyruvate oxidation, the electron donor is ________ and the electron acceptor is ___________
pyruvate; NAD+
__________ can be transported across both membranes of the mitochondrion to be further metabolized, but _________ cannot
pyruvate; glucose
In glycolysis, ATP is synthesized by
substrate level phosphorylation
in eukaryotic cells, glycolysis occurs in
the cytoplasm
in addition to destabilizing glucose for the subsequent breakdown, what else does phosphorylation of glucose do
traps glucose inside the cell
what is the fully oxidized product that results from the pyruvate oxidation stage of cellular respiration
carbon dioxide
glycolysis is:
anaerobic
of the 6 carbons in a starting molecule of glucose, at the completion of pyruvate oxidation, __________ carbons are fully oxidized to __________, while __________ carbons remain in ____________.
two, CO2, four, acetyl groups
what is a product of at least one of the processes of cellular respiration
water
a single molecule of glucose requires ______ turns through the citric acid cycle for its chemical energy to be completely harvested
2
tracing the metabolism of one glucose molecule, how many carbon atoms are fully oxidized to the CO2 at the completion of the pyruvate oxidation stage
2
what is the net product of glycolysis
2 pyruvate
tracing the metabolism of one glucose molecule, how many carbon atoms are available for further oxidation at the completion of the pyruvate oxidation stage
4
what is the result of substrate-level phosphorylation
ATP being produced
each molecule of acetyl-CoA that enters the citric acid cycle carries two of the carbon atoms from the original starting glucose molecule. These carbon atoms will ultimately leave the citric acid cycle as carbon atoms in which of the following: CO2 NADH FADH2 ATP oxaloacetate
CO2
what is the fully oxidized product that results from the pyruvate oxidation stage of cellular respiration
CO2
during the citric acid cycle, what happens to coenzyme A that is part of acetyl-CoA
It is recycled and for use in other reactions
what product of the pyruvate oxidation stage of cellular respiration will have two electrons that are lost from pyruvate
NADH
when a single pyruvate is converted to acetyl-coA during pyruvate oxidation, the other products of the reaction are
NADH and CO2
during the pyruvate oxidation stage of cellular respiration, which of the following occurs the oxidation of pyruvate the formation of acetyl-CoA the formation of Co2 the formation of NADH All of the above
all of the above
the breakdown of fatty acids takes place by a process called
beta-oxidation
in cellular respiration, oxygen
gains electrons and is reduced
proteins can be broken down to extract energy. They are typically broken down into amino acids, which then enter cellular respiration via
glycolysis or the citric acid cycle
which statement describes the proton gradient generated by the electron transport chain it contains electrochemical gradient it contains a great deal of kinetic energy it results from differences in the concentration of hydroxide ions the concentration is highest in the hydrophobic center of the inner membrane the concentration is highest in the hydrophobic center of the inner membrane the concentration is highest in the hydrophobic center of the outer membrane
it is an electrochemical gradient
pyruvate oxidation is an important stage in cellular respiration because
it links glycolysis with the citric acid cycle
during pyruvate oxidation, pyruvate is broken down into CO2 and an acetyl group. The CO2 is
less energetic than the acetyl group
the chemical bonds of carbohydrates and lipids have high potential energy because
many of these bonds are C-C and C-H bonds, in which electrons are shared equally between atoms
true or false: conditions that reduce the strength of the proton gradient across the inner mitochondrial membrane slow the production of ATP by ATP synthase
true
although glycolysis produces four molecules of ATP by substrate-level phosphorylation, the net gain of ATP for the cell is two molecules. This is because:
two molecules are used in the initial stage