What types of cells form epidermal tissue in plants? State the modifications in epidermal tissue in leaves, roots, desert plants, and older trees.

The epidermis is one single layer of tissue that covers the plant. It's main function is to protect it from the environment and absorb the water from the ground. The epidermal tissue itself consists of two different types or layers of cells commonly regarded as the upper and the lower epidermis. The epidermal cells are connected and make the plant stronger and more resistant to outer damage and infections. They cover the stem, the root, the seed, the leaves, the flower, and the fruit of the plant.
In various older botanical books and studies, the epidermal cells were called the parenchyma cells; however, these were later established as part of the ground tissue. The ground tissue (mesophyll) is located between the upper and the lower epidermis—this is where photosynthesis happens. The other tissue is called vascular tissue and it is responsible for providing the plant with water by absorbing it from the ground.