Question

The sugarcane plant has
A. Dumb-bell shaped guard cells
B. Pentamerous flowers
C. Reticulate venation
D. Capsular fruits

Answer 1

Hint: Guard cells control the opening and closing of stomata. Being a monocot plant, the sugarcane plant also has guard cells which are more efficient physiologically.

Complete answer: A Guard cell is a semilunar or kidney-shaped cell that surrounds stomata (the minute apertures of the epidermis).
Stomata are responsible for the transpiration of plants. Guard cells contain chloroplasts and these are living cells. They control the opening and closing of stomata aperture.
Sugarcane is a monocot plant. Like other monocot plants (e.g. maize), the sugarcane plant also has dumb-bell shaped guard cells.
Physiologically the dumb-bell shaped guard cells are more efficient as they require few solutes and less water to provide a desirable increase in the stomata apertures.

So, the correct option is A. Dumb-bell shaped guard cells.

Note: There are two types of guard cells, viz.
1) kidney-shaped guard cells and
2) dumb-bell shaped guard cells. In dicot plants, the kidney-shaped guard cells surround the stomata. The dumb-bell-shaped guard cells are found in monocots and grasses.
Pentamerous flowers, Reticulate venation, and capsular fruits –these are features of dicot plants.