On the bark of woody plants, there are some lens-shaped or egg-shaped pores present called lenticels. It functions as a pore allowing for the interchange of gases between the interior tissue and the surrounding air. Lenticels are the pores of outer plant tissue that provide a direct exchange of gases between internal plant tissues and the atmosphere.
(i) For the convenience of gaseous exchange cork cambium, in different places, produces thin-walled round parenchymatous cells instead of cork tissue
(ii) Due to the formation of parenchymatous cells, cell division occurs rapidly in them. Thus, a pressure falls on epidermal tissue and the epidermal cells rupture and forms lens-shaped pores.
(iii) The parenchymatous cells below the lens-shaped pores are known as complementary cells. These lens-shaped pores and the area of complementary cells lying below the lens-shaped pores are known as lenticels.
It functions as a pore allowing for the interchange of gases between the interior tissue and the surrounding air. Internal plant tissue is impermeable to gases without lenticel.
(i) The main function of lenticel is to perform gaseous exchange between air and inner tissues.
(ii) Often a little transpiration may occur through lenticels.
(iii) Lenticels like Stomata help in transpiration. Called Lenticular transpiration.
(iv) Lenticels are active during the night when stomatal transpiration stop.