What do the guard cells do?

The chief role of guard cells is to prevent an excess loss of water through respiration, allowing the plant to trade oxygen and carbon dioxide without becoming dehydrated. Guard cells are part of the system that maintains drought resistance in plants.

Explanation:

one is through turgidity. this occurs before ground tissue ( collenchyma

and sclerenchyma cells) become well

developed to give structural support to the plant as it grows bigger. the xylem

tissue (composed of rigid tissue) of the young

plant render this support and also maintaining osmotic turgidity of the surrounding

plant cells.