Practice question · Multiple choice
Why do plants in cold or dry climates often have narrower xylem vessels despite the enormous flow advantage of wide ones?
Hints
- Consider what happens to a wide column of water held under tension.
- An air bubble forming in a wide vessel disables it permanently.
Show the answer
B. Wide vessels are far more vulnerable to cavitation breaking the water column
Why
A wide column under tension is much more likely to cavitate, and a cavitated vessel is permanently lost. Freezing and drought both promote bubble formation, so plants in those climates trade conducting capacity for safety.
Practise Plant Ground and Vascular Tissues
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More questions on Plant Ground and Vascular Tissues
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