Respiration in Plants

Are tiny openings on the surface of leaves through which plants get oxygen from the atmosphere.

Plants don’t need oxygen during the day when it is provided through photosynthesis.

A/ The gas exchange mechanisms in plants are (1.)stomata and (2.) lenticels.

1. The stoma is a tiny structure that is formed by the differentiation of the epidermal tissue and it plays a role in the exchange of O2 and CO2 between the leaf’s tissue and the atmosphere. 2. A stoma is composed of a pair of bean-like cells known as guard cells with a space between them, known as the stomal opening. 3. The inner walls of the stoma’s guard cells are thicker than the outer walls. This difference has a role in the opening and closure procedure of stomata.

1. The epidermis of the plant forms a protective layer on the surface of young, tall plants and the outer tissue becomes woody as the plant matures and ages. 2. The stomata lose their ability to function and are replaced by lenticels. 3. Lenticels maintain gas exchange between the woody plant and the atmosphere and are found mostly on the roots, stems and branches.

Maintain gas exchange between the woody plant and the atmosphere.