What structure of the guard cells allows them to expand outward instead of spherically when inflated with water?

Question

Quizplus · Accepted Answer

The thick inner walls that border the stomata form a hinge-like structure which allows the guard cells to expand outward instead of spherically when inflated with water. This is what causes the opening of the stomata, allowing for gas exchange in plants. The thin outer walls in contact with epidermal cells play a role in helping the guard cells to change their shape, but do not directly contribute to their ability to expand outward.

What Structure of the Guard Cells Allows Them to Expand