Question

Bulliform cells are
A. Water filled and highly vacuolated epidermal cell
B. Prokaryotic cell
C. Eukaryotic cell
D. Ball like parenchymatous cells

Answer 1

Hint: These cells are proposed to be involved in the folding and unfolding of plant leaves in order to manage the intensity of light and reduce the total loss of water.

Complete Answer:
- Bulliform cells or motor cells are bubble-shaped, large, epidermal cells that appear in groups on the upper layer of the leaves of many monocots.
- The cells are present on the upper layer of the leaf. They are usually available near the mid-vein part of the leaf and are large, empty and colourless.
- Bulliform cells are so called because of the peculiar shape of the bubble. It occurs mainly on the upper layer of the leaves in the grasses.
- The water present in these cells helps to maintain its shape but the loss of turgor pressure during stress allows the leaves to roll up. During the drought, the loss of water through the vacuoles induces bulliform cells to close.
- Therefore, the two edges of the leaves of many grass species are folded towards each other. Once sufficient water is available, the cells widen and the leaves open again.

Thus, the correct answer is option A i.e., Water filled and highly vacuolated epidermal cell.

Note: Bulliform cells help roll leaves to avoid water loss through transpiration. They control the transpiration process. The leaves are also unrolled under favourable conditions. Bulliform cells are mainly found in grass.