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Question
Droplets of water may sometimes be seen along the margins of the leaves of a banana plant, growing in wet soil, in the mornings. Are these dew drops? Comment upon your answer.
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Solution
No, they are not dew drops.
This is water given out by the plant body through guttation. Since the banana plant is growing in humid environment, transpiration is hampered. But the roots continue to absorb water from the soil. This builds up a huge hydrostatic pressure within the plant and forces out the excess water from the hydathodes, which are pores present at the tips of veins in the leaf. This is observed especially during the mornings.
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Match the terms given in column A with column B:
| Column A | Column B | ||
| (a) | Hydathodes | (i) | Photosynthesis |
| (b) | Stomata | (ii) | Respiration |
| (c) | Cuticle | (iii) | Regulates opening and closing of stomata |
| (d) | Lenticels | (iv) | Reduces loss of water |
| (e) | Guard cells | (v) | Guttation |
Define the following term:
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