Question

opening present on the bark of old stems

Answer 1

opening is called lenticles for gaseous exchange

Answer 2

Answer:

The opening present on the bark of old stems are called lenticels.

Explanation:

Lenticels are minute openings that are found in the bark of old stems. The lenticels are basically a type of porous tissues that are are formed of the large intercellular spaces in the periderm of the woody, old, secondary thickened stems or barks and often in the roots. The primary function of the lenticels is to help in the process of gaseous exchange, although, at times, lenticels also promotes lenticular transpiration.