Autotrophs take up water from the soil through their roots in terrestrial plants.

Gaseous exchange occurs across the surface of stems, roots, and leaves, ensuring efficient gas exchange for photosynthesis and other plant processes.

Guard cells regulate the opening and closing of stomatal pores; they swell with water, causing the pore to open, and shrink to close it, controlling gas exchange and water loss.

The opening and closing of stomatal pores, regulated by guard cells, control gaseous exchange, preventing excessive water loss while facilitating the intake of carbon dioxide for photosynthesis.

The plant obtains carbon dioxide through tiny pores called stomata present on the surface of leaves.