Question

Write the short notes on the following: (a) Bulliform cells (b) East fibres (c) Hydathode (d) Open vascular bundle (e) Intercalary meristems.

Answer 1

• $Bulliformcells$:

Bulliform cells are large, bubble-shaped epidermal cells that occur in groups on the upper surface of the leaves of many monocots. These cells are present on the adaxial or the upper surface of the leaf. They are generally present near the midvein. These cells are large, empty and colorless.

• $Eastfibres$:

East fibers are similar in that they are sclerenchyma cells that serve as part of the plant skeleton. They are predominantly long cells with thick walls and small cavities and usually pointed ends. The walls often contain lignin as well as cellulose.

• $Hydathode$:

A hydathode is a type of pore, commonly found in angiosperms, that secretes water through pores in the epidermis or leaf margin, typically at the tip of a marginal tooth or serration.

• $Openvascularbundle$:

1. The vascular bundle contains a strip of cambium between phloem and xylem.
2. Phloem and xylem do not lie in direct contact with each other.
3. Due to the activity of cambium, original or primary phloem and xylem move away from each other. Secondary phloem and secondary xylem are formed in between.
4. Open vascular bundles occur in dicot and gymnosperm stems.
5. Open vascular bundles can be collateral and bi-collateral.

• $Intercalarymeristems$:

Intercalary meristems are capable of cell division, and they allow for rapid growth and regrowth of many monocots. Intercalary meristems at the nodes of bamboo allow for rapid stem elongation, while those at the base of most grass leaf blades allow damaged leaves to rapidly regrow.