Definition - What does Cortex mean?
The term cortex refers to the outermost layer of cells on a plant’s stem or root. The cortex has the ability to transport nutrients into the core of the root. It uses diffusion to achieve the transport. It also stores nutrients in the form of starch.
The cortex acts as a protective covering on plant and is often waterproof. Depending on the type of plant, the cortex can also store carbohydrates, tannins, essential oils, and resins.
MaximumYield explains Cortex
The cortex in a plant is composed of porous tissue. The porous tissue is called the aerenchyma. It contains a variety of air spaces.
The cells of the cortex play a crucial role in the plant’s life. They convert the carbon dioxide and water that the plant absorbs into simple carbohydrates which the plant then uses for photosynthesis.
On woody stem plants, trees, and roots, the cortex produces a protective, waterproof layer which is often referred to as bark. Often as a plant ages, the cortex becomes thicker and more impenetrable.
Sometimes the cortex is referred to as the plant's skin, but this is an oversimplification. Some of the outer cortical cells may contain chloroplasts.