Which of the following helps some hydrophytes to thrive in wetlands and marshes where water level fluctuates time to time?

The correct answer is option 3.

Key Points

• Aerenchyma tissue is a type of specialized parenchyma tissue found in many aquatic and semi-aquatic plants (hydrophytes).
• It contains large air spaces that allow:
  • Buoyancy (helps the plant float)
  • Efficient gas exchange, especially oxygen transport to submerged tissues
  • Survival in anaerobic (oxygen-poor) conditions such as marshes and wetlands

Additional Information

• Rhizomatous roots: Help in vegetative propagation but not directly in coping with fluctuating water levels.
• Submergent roots: Common in underwater plants, but don’t offer buoyancy or gas transport.
• Rhizophores: Specialized roots found in some terrestrial plants like Selaginella, not related to marsh adaptation.
• Thus, Aerenchyma is the key adaptation enabling hydrophytes to survive in challenging wetland ecosystems.