Difficulty: Easy
Correct Answer: more slowly than the normal fruit
Explanation:
Introduction / Context:
One of the earliest commercial plant biotechnology traits (for example, the Flavr Savr tomato) used antisense RNA to reduce expression of polygalacturonase, an enzyme that degrades pectin in cell walls, thereby slowing fruit softening.
Given Data / Assumptions:
Concept / Approach:
Reducing polygalacturonase activity stabilizes the cell wall matrix, maintaining firmness longer. Ethylene may still rise, but downstream cell wall disassembly is tempered, producing a measurable delay in texture changes.
Step-by-Step Solution:
Verification / Alternative check:
Postharvest studies reported improved firmness retention and extended shelf life in antisense PG lines compared with controls.
Why Other Options Are Wrong:
Common Pitfalls:
Confusing ethylene suppression strategies with cell-wall enzyme suppression; both can delay ripening but via different mechanisms.
Final Answer:
more slowly than the normal fruit.
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