One type of it is stem cells. Queiscent cells are adult cells which do not divide, but under certain stimulation when it is needed, it can undergo cell division. One example are hepatocytes (liver cells).Permanent cells are cells that do not divide at all and have no such capabilities.ne type of it is stem cells. Queiscent cells are adult cells which do not divide, but under certain stimulation when it is needed, it can undergo cell division. One example are hepatocytes (liver cells).
Hairs trap a still layer of air to slow the rate of water vapor loss. Epidermal tissue has stomatal guard cells that regulate transpiration. Vascular tissue has a role in internal transport of water from root to leaf. The xylem is lignified to control water dispersal from the column. Limiting water exit to the plasmodesmata (desmodesmata) channels through cell walls.
Plants have many adaptations to cope with the lack of water. Some desert plants, such as the barrel cactus, have expandable stems for storing water. Other plants have adaptations that reduce water loss from their leaves, the part of a plant through which most of the water is lost. Still others have a waxy coating on the leaves, or have small leaves, that reduce the surface area exposed to the drying elements. In many cases, desert plants have no leaves at all.