Final answer:
The opening and closing of stomata in plants are regulated by environmental factors and the turgor pressure of guard cells. This process allows plants to regulate gas exchange, control transpiration and photosynthesis, and maintain water balance.
Step-by-step explanation:
The opening and closing of stomata in plants is regulated by the turgor pressure of specialized cells called guard cells. When the guard cells are flaccid, stomata close; and when they are swollen with water, stomata open. This process is influenced by various environmental factors, such as light, carbon dioxide concentration, water deficit, darkness, and pollutants.
Specifically, an increase in carbon dioxide concentration and light can trigger stomata to open, while water deficit, darkness, microbes, ozone, and pollutants can cause stomatal closing. The opening and closing of stomata allow plants to regulate gas exchange, control transpiration and photosynthesis, and maintain water balance.