Gas exchange on a stem primarily occurs through small openings called lenticels, which are found on the surface of the stem. These lenticels allow for the exchange of gases, such as oxygen and carbon dioxide, between the internal tissues of the plant and the atmosphere. Unlike leaves, stems have a more limited surface area for gas exchange, but lenticels play a crucial role in facilitating this process for the plant's overall respiration.
The gas occurs by simple diffusion through the cells.
the alveolus
in the leave
gills
gas exchange occurs between the thin walls of the alveoli and the thin walls of the capillaries
in their gills.
In the alveoli
lungs
Gas exchange does not occur in the pleura. The pleura is a membrane that lines the outside of the lungs and inside of the chest cavity. Gas exchange, where oxygen is taken in and carbon dioxide is removed, happens in the alveoli of the lungs.
Capillaries
Between the avioli and the lungs.
It's a pore found in the epidermis of the leaf and stem of a plant, used for gas exchange.