Question 42·200 Super-Hard SAT Reading Questions·Expression of Ideas
While researching a topic, a student has taken the following notes:
- Tardigrades can survive extreme dehydration by entering a state called anhydrobiosis.
- During anhydrobiosis, tardigrades synthesize trehalose, a sugar that replaces water within their cells.
- Trehalose forms a glass-like matrix that stabilizes cellular structures in the absence of water.
- When water becomes available again, trehalose dissolves and normal metabolic activity resumes.
The student wants to explain how tardigrades survive periods of dehydration. Which choice most effectively uses relevant information from the notes to accomplish this goal?
For Rhetorical Synthesis questions, restate the goal (here, explain the mechanism of dehydration survival). Then identify the most distinctive notes (anhydrobiosis, trehalose replacing water, glass-like matrix) and choose the option that accurately combines those points without changing the sequence or shifting key actions to the wrong time.
Hints
Look for a full mechanism
Pick the option that explains what they do during dehydration that protects their cells, not just what happens after water returns.
Use the unique detail
One note is especially specific: trehalose forms a glass-like matrix that stabilizes cellular structures. The best answer should include that idea.
Check the sequence
The notes say trehalose is synthesized during anhydrobiosis. Be cautious of any choice that flips that order.
Avoid answers that shift the timing
Cross out choices that make trehalose’s key role happen after rehydration starts rather than during dehydration.
Step-by-step Explanation
Restate the goal
The student needs to explain how tardigrades survive periods of dehydration, so the best sentence must describe both the process (anhydrobiosis) and the mechanism (what trehalose does) that makes survival possible.
Assemble the key mechanism from the notes
From the notes: tardigrades enter anhydrobiosis; during it they synthesize trehalose, which replaces water in cells and forms a glass-like matrix that stabilizes cellular structures; when water returns, trehalose dissolves and normal metabolic activity resumes.
Eliminate choices that omit or distort key notes
Eliminate any option that leaves out what trehalose does (replacing water and forming a stabilizing matrix) or that changes the timing described in the notes (these events happen during anhydrobiosis, not after rehydration begins).
Select the choice that uses the most relevant notes accurately
The best choice is: Tardigrades survive dehydration by entering anhydrobiosis and synthesizing trehalose, which replaces water and forms a glass-like matrix that stabilizes cells.