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AP Bio Practice Exam 1 With Complete Questions And Answers
Question :Humans produce sweat as a cooling
mechanismto maintain a stable internal temperature.Whichof the following best explains how the propertiesof water contribute to this physiological process?
Correct answer:The high heat of vaporization of
waterallows the body to remove excess heatthrough a phase change of water fromliquid to gas
Question :A student placed a semipermeable
membraneinside a U-shaped channel with two chambers,as shown. The membrane permits the movementof water but not salt. The student wants to varythe rate of osmosis that occurs across themembrane.Which of the followingexperimental designs will result in the fastest netrate of water movement into chamber A?
Correct answer:Placing salt water in chamber A
anddistilled water in chamber B
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Question :Which of the following best describes the role
ofwater in photosynthesis?
Correct answer:Water molecules donate electrons to
theelectron transport chain
Question :What evolutionary advantage
doescompartmentalization of core metabolicprocesses offer eukaryotes?
Correct answer:Evolution of a nucleus in
eukaryotesseparates the processes of transcriptionand translation and they can be regulatedseparately
Question :Which of the following best describes
thecellular location where pyruvate dehydrogenaseis most likely active?
Correct answer:The mitochondrial matrix
Question :The maximum production rate of acetyl-
CoAunder condition 1 is closest to which of thefollowing?
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Correct answer:1 micromole/sec
Question :Which of the following observations
providesthe best evidence that acetyl-CoA negativelyregulates pyruvate dehydrogenase activity?
Correct answer:The rate of the pyruvatedehydrogenase-
catalyzed reaction isslower in the presence of a higherconcentration of acetyl-CoA
Question :Pyruvate dehydrogenase deficiency is a
geneticdisease most commonly linked to a mutation inthe a -subunit of the mitochondrial enzyme thatcauses the enzyme to cease functioning. As aresult of the mutation, affected individuals buildup dangerous amounts of lactic acid. Which ofthe following best explains the buildup of lacticacid in individuals with the mutation?
Correct answer:Cells undergo fermentation
becausepyruvate cannot be metabolized toproceed into the Krebs cycle
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Question :The diagram shows how water can adhere to
thexylem in the stems of plants, which contributesto water movement in the plant. Which of thefollowing best explains how water is able tomove upward from the roots of a plant, throughits xylem in the stem, and out to the leaves?
Correct answer:Water and the xylem are both polar.
Watermolecules have the ability to formhydrogen bonds with each other and withthe walls of the xylem
Question :Protein X activates gene expression only in
cellsexposed to a specific signaling molecule. In astudy, researchers determined the intracellularlocation of Protein X in cultured cells bothbefore and after exposing the cells to thesignaling molecule. The results of the study areshown in the diagram
Correct answer:Protein X is a transcription factor
Question :The hormone prolactin has varying effects
inmany different animal species. All vertebratesproduce