AP Biology 2024 Practice Test Exam Questions With Correct Answers 100% Verified.

AP Biology 2024 Practice Test Exam Questions With Correct Answers 100% Verified. 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? - answerThe high heat of vaporization of water allows the body to remove excess heat through a phase change of water from liquid to gas. (Water has a high heat of vaporization. Sweat produced by the body decreases the temperature of the body by absorbing a large quantity of heat energy during the liquid to gas phase change. 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? - answerPlacing salt water in chamber A and distilled water in chamber B (Distilled water from chamber B will move to chamber A because chamber A has a higher solute concentration.) Which of the following best describes the role of water in photosynthesis? - answerWater molecules donate electrons to the electron transport chain. (Electrons are released from water molecules and donated to photosystem II) What evolutionary advantage does compartmentalization of core metabolic processes offer eukaryotes? - answerEvolution of a nucleus in eukaryotes separates the processes of transcription and translation and they can be regulated separately. (The evolution of a nuclear membrane that contains genetic material allowed for cells to separate the copying of genetic material and the production of proteins.) 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? - answerWater 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. (Water has a high surface tension as a result of the hydrogen bonds that water molecules form between each other because both the xylem and the water are polar.) 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. The diagram shows an inverted colored cell. - answerProtein X is a transcription factor. (The movement of Protein X from the cytoplasm to the nucleus indicates that it 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? - answerProlactin is a homologous hormone because it has a common origin but different functions in various species. (Prolactin is not highly conserved, because it has multiple functions in different organisms. Therefore, its presence in these organisms indicates a common origin.) A particular gene has two alleles, a dominant allele A and a recessive allele a. The frequency of allele A is 0.55. If the population is in Hardy-Weinberg equilibrium with respect to the gene, then what is the expected frequency of genotype Aa? - answer0.495 (This option correctly calculates the heterozygote frequency from the dominant allele frequency) Oncogenes are genes that can cause tumor formation as a