Day time loss of water in the vapour form from stomata is a trade off for intake of

In the day-time, when photosynthesis occurs, the guard cells are turgid while in the evening, regardless of the availability of water, these guard cells lose turgidity. When they are turgid, stomata open, and carbon dioxide enters freely. When they are flaccid, carbon dioxide is largely excluded, but water loss is also retarded. hence, the daytime loss of water in the vapor form from stomata is a trade-off for intake of carbon dioxide.