Question

Large nearly empty, colourless cells present on the upper surface of grass leaf are

• A. Accessory cells
• B. Bulliform cells
• C. Palisade parenchyma
• D. Spongy parenchyma
• E. Passage cells

Answer 1

The correct option is B Bulliform cells

A.Accessory cells - epidermal cells present around the stomata are called Accessory cells. They help in stomatal transpiration.

B.Bulliform cells - The large, colourless, water filled, hygroscopic, epidermal cells present in the upper epidermis of grass leaves are called Bulliform cells or Motor cells. They involve in the rolling of leaf lamina during dry conditions and unrolling of leaf lamina during wet conditions.

C.Palisade parechyma - It is present below the upper epidermis. In this, cells are cylindrical, closely arranged, with more number of chloroplasts.

D.Spongy parenchyma - It is present above the lower epidermis. In this cells are loosely arranged with big inter cellular spaces, less number of chloroplasts.

E.Passage cells - Endodermal cells with out casparian thickenings are called Passage cells. These are present opposite to the protoxylem cells. These are meant for transport of water from cortex to stele.

So, the correct option is 'Bulliform cells'.