stoma closes, water begins to build up inside leaf so two feeback loops work to allow stoma to open when water is available and when light is available and when CO 2 is being used.
(stoma; closes; ) (water; begins; ) (water; is; available) (light; is; available) (CO 2; is being used; )
stoma water water light CO 2
closes begins is is is being used
available
available