JAMB - Biology (2007 - No. 18)
The opening and closing of the stoma are regulated by
transpiration
respiration
diffusion
osmosis
Explicació
The process that controls the opening and closing of the stoma is osmosis, which occurs within the specialized cells called "guard cells" that surround the stoma; when water flows into the guard cells, they swell and the stoma opens, while when they lose water, they shrink and the stoma closes.