Daylight
Increase in temperature causes stomata to open. A hydathode is a type of secretary tissue in leaves, usually of Angiosperms , that secretes water through pores in the epidermis or margin of leaves, typically at the tip of a marginal tooth or serration. They probably evolved from modified stomata.
stomata which are tiny spots on the underside of the leaf
They shut because with the stomata open it is too drafty and the plant can't get to sleep.
Transpiration
The tiny holes in leaves through which carbon dioxide enters are called stomata. Stomata are small pores located on the surface of leaves that open and close to allow for gas exchange, including the intake of carbon dioxide for photosynthesis.
The leaves would dry out
Carbon dioxide enters plants through small openings called stomata, which are typically found on the underside of leaves. Stomata open and close to regulate the flow of gases in and out of the plant, allowing carbon dioxide to enter for photosynthesis.
At night, the leaves of C3 plants close their stomata and wait until the sunlight. For CAM plants, this is when the plants open their stomata and allow the carbon dioxide to come in.
Plants breath through stomates. they are microscopic openings covering the leaves that open and close bringing in CO2 and out oxygen. This gives us 29 percent of our oxygen while the other percentage (71) is from phytoplankton
Stomata
Depending on the environment of the plant, stomata will open and close at different times. In hot, dry environments stomata will open around dusk and dawn to minimise water loss. In Wet environments stomata will open during the day as needed