Plant cells are a form of eukaryotic cells with true nucleus and organelles. Various types of plant cells are -xylem cells, phloem cells ,parenchyma cells, collenchyma cells and sclerenchyma cells. These cells distinguish plants from animal kingdoms.
In desert plants like cactus, they have an exquisite set of adaptations for optimal water management. They have thickened stem tissues with thin-walled parenchyma cells so a lot of water can be stored in stems.