Question

Grass leaves curl inwards during very dry weather. Select the most appropriate reason from the following:

• A. Tyloses in vessels
• B. Closure of stomata
• C. Flaccidity of bulliform cells
• D. Shrinkage of air spaces in spongy mesophyll

Answer 1

The correct option is C Flaccidity of bulliform cells

Bulliform cells become flaccid due to water loss during dry weather. Hence the leaves curl inward to minimise loss of water.

Tyloses are outgrowths on parenchyma cells of xylem vessels of secondary heartwood. This occurs during drought conditions.

Shrinkage of air spaces in spongy mesophyll results in decrease in buoyancy of plant.