A balloon expands and shrinks which type of cell does the balloon best model

Hello there, friend! A simple answer is below.

The answer is Guard Cell.

Explanation:

Guard cells are specialized plant cells that regulate gas exchange in the epidermis of leaves, stems, and other organs. They are generated in pairs, with a stomatal hole forming the space between them. When water is abundant and the guard cells are turgid, the stomatal holes are the biggest; when water is scarce and the guard cells become flaccid, the stomatal apertures close.

the answer would be 3

lizards have adapted to life in the desert. some desert lizards have toes with spiny scales to them run across the sand without sinking. some use the sand to hide from predators, or to search for small animals that they prey upon.