Question

Which of the following feature indicates the hydrophytic nature of Equisetum?

• A. Presence of ridges and grooves on the stem
• B. Presence of sunken stomata
• C. Vallecular canal and central pith cavity
• D. Presence of well developed sclerenchymatous hypodermis

Hint:

Vallecular canals and pith cavities are aerenchyma-like air spaces that aid gas exchange in submerged/wetland plants.

Answer 1

The Correct Option is C

Step 1: Concept
Hydrophytic adaptations in Equisetum (horsetails).

Step 2: Meaning
Hydrophytes are adapted to live in waterlogged or aquatic environments and show specific structural adaptations for gas exchange.

Step 3: Analysis
(A) Ridges and grooves: common structural feature, not hydrophytic.
(B) Sunken stomata: a xerophytic adaptation (reduces water loss).
(C) Vallecular canals and central pith cavity: large air spaces for gas exchange and buoyancy --- hydrophytic adaptation.
(D) Sclerenchymatous hypodermis: provides mechanical support, not hydrophytic.

Step 4: Conclusion
Vallecular canals and central pith cavity indicate the hydrophytic nature of Equisetum. Final Answer: (C)