A team of biologists led by Jae-Hoon Jung, Antonio D. Barbosa, and Stephanie Hutin investigated the mechanism that allows Arabidopsis thaliana (thale cress) plants to accelerate flowering at high temperatures. They replaced the protein ELF3 in the plants with a similar protein found in another species (stiff brome) that, unlike A. thaliana, displays no acceleration in flowering with increased temperature. A comparison of unmodified A. thaliana plants with the altered plants showed no difference in flowering at 22° Celsius, but at 27° Celsius, the unmodified plants exhibited accelerated flowering while the altered ones did not, which suggests that ______blank
","stem_html":"Which choice most logically completes the text?
","rationale_html":"Choice C is the best answer because it most logically completes the text’s discussion of accelerated flowering in A. thaliana plants. The text indicates that A. thaliana plants show accelerated flowering at high temperatures. To investigate the mechanism for this accelerated flowering, biologists replaced the ELF3 protein in one group of A. thaliana plants with a similar protein found in another plant species that doesn’t show accelerated flowering. The team then compared these modified plants to A. thaliana plants that retained their original ELF3 protein. The text states that the two samples of plants showed no difference in flowering at 22° Celsius, but at 27° Celsius the unaltered plants with ELF3 showed accelerated flowering while the plants without ELF3 didn’t. If accelerated flowering at the higher temperature occurred in the A. thaliana plants with ELF3 but not in the plants without the protein, then ELF3 likely enables A. thaliana to respond to increased temperatures.
Choice A is incorrect because the text doesn’t mention whether any plants other than A. thaliana and stiff brome show temperature-sensitive flowering, so there is no support for the idea that this type of flowering is unique to A. thaliana. Choice B is incorrect because the text discusses the effects of ELF3 and not the production of it. There’s nothing in the text to suggest that the amount of ELF3 in A. thaliana varies with temperature. Choice D is incorrect. While the text states that there was no difference in the flowering of modified and unmodified A. thaliana plants at 22° Celsius, there’s no suggestion that A. thaliana only begins to flower at 22° Celsius; the text doesn’t mention a specific temperature threshold required for A. thaliana flowering.
","correct_answer":["C"],"has_media":false,"has_mathml":false,"has_table":false,"source_created_at":"2023-08-02T20:25:59.314000+00:00","source_updated_at":"2023-08-02T20:25:59.314000+00:00","options":[{"label":"A","content_html":"temperature-sensitive accelerated flowering is unique to A. thaliana.
","ord":0},{"label":"B","content_html":"A. thaliana increases ELF3 production as temperatures rise.
","ord":1},{"label":"C","content_html":"ELF3 enables A. thaliana to respond to increased temperatures.
","ord":2},{"label":"D","content_html":"temperatures of at least 22° Celsius are required for A. thaliana to flower.
","ord":3}],"attribution":{"source_id":"cb_question_bank","source_name":"College Board digital SAT question bank (community dump)","rights_holder":"College Board","canonical_url":"https://satsuitequestionbank.collegeboard.org/","retrieved_from":"https://raw.githubusercontent.com/mdn522/sat-question-bank/main/data/cb-digital-questions.json","attribution":"SAT practice questions © College Board, from the official SAT Suite Question Bank. Retrieved via the community dump at github.com/mdn522/sat-question-bank.","disclaimer":"SAT® and PSAT/NMSQT® are trademarks registered by the College Board, which is not affiliated with, does not sponsor, and does not endorse this project.","license":"College Board copyright; source repository carries no licence. Local use only.","redistributable":false,"item_count":2017}}