Question

The breathing and respiration in woody stem of a plant takes place through ______.

Options

• root hair

• lenticels

• closed stomata

• open stomata

Answer 1

The breathing and respiration in woody stem of a plant takes place through lenticels.

Explanation:

In old, mature, woody stems, the epidermis is replaced by a protective layer called bark (or cork). Since cork cells are dead and largely impermeable to gases, normal gaseous exchange through the surface is restricted. Stomata are usually absent or non-functional in these woody parts. Therefore, the bark develops specialised structures called lenticels, which are small, permanently open pores that allow the exchange of oxygen and carbon dioxide required for respiration.