in the leave
The gas occurs by simple diffusion through the cells.
the alveolus
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.
Seaweed does not breathe, instead it respires by gaseous exchange through water
Gaseous exchange takes place when the volume of the chest cavity is increased or decreased.