AP Biology Unit 3 Cellular Energetics Exam Test
Questions And Answers Verified 100% Correct
A scientist claims that Elysia chlorotica, a species of sea slug, is capable of
photosynthesis.
Which of the following observations provides the best evidence to support the claim? -
ANSWER Elysia chlorotica grows when exposed to light in the absence of other food
sources.
Phosphofructokinase (PFK) is an enzyme that catalyzes the conversion of fructose
6phosphate to fructose 1,6-bisphosphate during glycolysis, as represented in Figure
1.
PFK can be allosterically inhibited by ATP at high concentrations.
Which of the following is the benefit of regulating glycolysis by the concentration of
ATP? - ANSWER Glycolysis proceeds when the intracellular concentration of ATP is
low, which provides ATP to drive cellular reactions.
Which of the following best predicts how the structure and function of pepsin will change
as it enters the small intestine? - ANSWER Pepsin will change in shape because of the
basic environment of the small intestine; therefore, its enzymatic activity will decrease.
To test the hypothesis that a particular plant synthesizes storage lipids by using
glyceraldehyde 3-phosphate (G3P) from photosynthesis, a researcher plans to use
radiolabeled precursors to track the molecules through the biosynthetic pathway. Which
of the following radiolabeled precursors is most appropriate for the researcher to use? -
ANSWER 14C-labeled CO2, because atmospheric carbon is fixed to carbohydrates by
photosynthesis
A researcher proposes a model of an enzyme-catalyzed reaction in which a reactant is
converted to a product. The model is based on the idea that the reactant passes
through a transition state within the enzyme-substrate complex before the reactant is
converted to the product.
Which of the following statements best helps explain how the enzyme speeds up the
reaction? - ANSWER The enzyme's active site binds to and stabilizes the transition
state, which decreases the activation energy of the reaction.
The enzyme hexokinase catalyzes the conversion of glucose to glucose-6-phosphate,
which is an important step in glycolysis. The reaction involves the transfer of a
phosphate group from ATP to glucose.
Questions And Answers Verified 100% Correct
A scientist claims that Elysia chlorotica, a species of sea slug, is capable of
photosynthesis.
Which of the following observations provides the best evidence to support the claim? -
ANSWER Elysia chlorotica grows when exposed to light in the absence of other food
sources.
Phosphofructokinase (PFK) is an enzyme that catalyzes the conversion of fructose
6phosphate to fructose 1,6-bisphosphate during glycolysis, as represented in Figure
1.
PFK can be allosterically inhibited by ATP at high concentrations.
Which of the following is the benefit of regulating glycolysis by the concentration of
ATP? - ANSWER Glycolysis proceeds when the intracellular concentration of ATP is
low, which provides ATP to drive cellular reactions.
Which of the following best predicts how the structure and function of pepsin will change
as it enters the small intestine? - ANSWER Pepsin will change in shape because of the
basic environment of the small intestine; therefore, its enzymatic activity will decrease.
To test the hypothesis that a particular plant synthesizes storage lipids by using
glyceraldehyde 3-phosphate (G3P) from photosynthesis, a researcher plans to use
radiolabeled precursors to track the molecules through the biosynthetic pathway. Which
of the following radiolabeled precursors is most appropriate for the researcher to use? -
ANSWER 14C-labeled CO2, because atmospheric carbon is fixed to carbohydrates by
photosynthesis
A researcher proposes a model of an enzyme-catalyzed reaction in which a reactant is
converted to a product. The model is based on the idea that the reactant passes
through a transition state within the enzyme-substrate complex before the reactant is
converted to the product.
Which of the following statements best helps explain how the enzyme speeds up the
reaction? - ANSWER The enzyme's active site binds to and stabilizes the transition
state, which decreases the activation energy of the reaction.
The enzyme hexokinase catalyzes the conversion of glucose to glucose-6-phosphate,
which is an important step in glycolysis. The reaction involves the transfer of a
phosphate group from ATP to glucose.
