Question

Leaves of many grasses are capable of folding and unfolding because they

• A. are very thin
• B. are isobilateral
• C. have specialized bulliform cells
• D. have parallel vascular bundles

Answer 1

The correct option is C have specialized bulliform cells

Monocot leaves have groups of larger, thin-walled, protruding and turgid cells around the regions of veins in the adaxial or upper epidermis. They are called bulliform or motor cells.

These cells are highly vacuolated and can store water, if available. However, the bulliform cells lose water and become flaccid, in case of water deficiency. The leaves get rolled up as a result of this to reduce the exposed surface.