Living organisms have an outside "container" that serves to protect the contents of the organism. In bacteria, the cell wall protects the bacteria's internal structures, such as the ribosomes and nucleoid, as well as helping keep the bacteria's shape, either spherical, rod-shaped or spiral with the exception of mycoplasma bacteria, which do not have cell walls. The skin, which consists of the outer epidermis and the underlying dermis, helps protect the human body from being damaged physically, helps protect the body from bacterial and viral infections and helps protect the body from damage from exposure to ultraviolet rays. Dermal tissue is the outside layer of a plant, with the exception of woody trees and shrubs, which are covered with bark for protection.
Plants have two organ systems. These systems are the shoot system, which is the part of the plant that lives above ground, such as stems and leaves, and the root system. The root system is the part of the plant that grows below the ground, including roots and tubers. In addition, plants are divided into three different tissue groups, vascular tissue, ground tissue and the dermal tissue.
Vascular tissue helps support the plant. In addition, vascular tissue distributes water, minerals, and food products from photosynthesis throughout the plant. Photosynthesis is the process that plants use to convert sunlight to carbohydrates for food. The two main components of vascular tissue are the xylem, which distributes water and minerals throughout the plant from the plant's roots, and phloem, which transports food through the plant.
Ground tissue is the tissue between the vascular tissue and the dermal tissue. In addition to being involved in photosynthesis, ground tissue helps provide the plant with support. This tissue, which consists mainly of parenchyma cells, also has the ability to store food and water.
Dermal tissue is the "outside" or outer part of a plant, which operates to control water and gas exchanges from the plant to the environment outside of the plant. The outside of the dermal tissue is called the epidermis. Epidermis produces a waxy layer called the cuticle which helps keep the plant from losing water. Another part of the epidermis that helps prevent water loss is the epidermal hair. Root hairs increase water intake into the plant while glandular hairs contain substances that the plants use to repel harmful insects.