AP Bio Practice Exam 1 Questions and Answers

AP Bio Practice Exam 1 Questions and Answers Humans produce sweat as a cooling mechanism to maintain a stable internal temperature. Which of the following best explains how the properties of water contribute to this physiological process? - Correct Answer ️️ -The high heat of vaporization of water allows the body to remove excess heat through a phase change of water from liquid to gas A student placed a semipermeable membrane inside a U-shaped channel with two chambers, as shown. The membrane permits the movement of water but not salt. The student wants to vary the rate of osmosis that occurs across the membrane. Which of the following experimental designs will result in the fastest net rate of water movement into chamber A? - Correct Answer ️️ -Placing salt water in chamber A and distilled water in chamber B Which of the following best describes the role of water in photosynthesis? - Correct Answer ️️ -Water molecules donate electrons to the electron transport chain What evolutionary advantage does compartmentalization of core metabolic processes offer eukaryotes? - Correct Answer ️️ -Evolution of a nucleus in eukaryotes separates the processes of transcription and translation and they can be regulated separately Which of the following best describes the cellular location where pyruvate dehydrogenase is most likely active? - Correct Answer ️️ -The mitochondrial matrix The maximum production rate of acetyl-CoA under condition 1 is closest to which of the following? - Correct Answer ️️ -1 micromole/sec Which of the following observations provides the best evidence that acetyl-CoA negatively regulates pyruvate dehydrogenase activity? - Correct Answer ️️ -The rate of the pyruvate dehydrogenase-catalyzed reaction is slower in the presence of a higher concentration of acetyl-CoA Pyruvate dehydrogenase deficiency is a genetic disease most commonly linked to a mutation in the a -subunit of the mitochondrial enzyme that causes the enzyme to cease functioning. As a result of the mutation, affected individuals build up dangerous amounts of lactic acid. Which of the following best explains the buildup of lactic acid in individuals with the mutation? - Correct Answer ️️ -Cells undergo fermentation because pyruvate cannot be metabolized to proceed into the Krebs cycle The diagram shows how water can adhere to the xylem in the stems of plants, which contributes to water movement in the plant. Which of the following best explains how water is able to move upward from the roots of a plant, through its xylem in the stem, and out to the leaves? - Correct Answer ️️ -Water and the xylem are both polar. Water molecules have the ability to form hydrogen bonds with each other and with the walls of the xylem Protein X activates gene expression only in cells exposed to a specific signaling molecule. In a study, researchers determined the intracellular location of Protein X in cultured cells both before and after exposing the cells to the signaling molecule. The results of the study are shown in the diagram - Correct Answer ️️ -Protein X is a transcription factor The hormone prolactin has varying effects in many different animal species. All vertebrates produce prolactin, which is involved in signal transduction pathways. In mammals, prolactin stimulates the production of milk in mammary glands. In fish, prolactin plays an important role in osmoregulation. In birds, prolactin is involved in lipid metabolism. Which of the following best explains the presence of prolactin in various vertebrate species? - Correct Answer ️️ -Prolactin is a homologous hormone because it has a common origin but different functions in various species Which of the following best describes the production of DMSP by coral and coral symbionts? - Correct Answer ️️ -A negative feedback mechanism that reverses the environmental change Which of the following best describes the effect of temperature on corals' ability to produce DMSP as shown in Figure 1 ? - Correct Answer ️️ -Both juvenile and adult corals produce less