In this lesson, you will learn about root hairs, which are the structures that allow a plant to get water and nutrients from the soil. They are a delicate but necessary component of a plant’s overall root system.
You may not know it, but you have likely eaten many roots in your lifetime. Carrots, beets, and turnips are actually the roots of plants, growing deep into the ground to provide nutrient storage and stability.
These types of roots are called taproots and are one long, vertical root that grows straight down into the ground.But even a taproot is more complex than just a single structure. Taproots give rise to lateral roots, which also store sugar and other nutrients that the plant will need later. These root branches also provide extra support for the plant, helping to anchor it even more securely in the ground.
Together, these various root parts compose an overall root system. And while they are responsible for much of the support and food storage, the actual absorption of nutrients comes through the root hairs, which are found at the root tips. Root hairs are found in large quantities in these areas and greatly increase the surface area of a root.
Function of Root Hairs
Root hairs are a very simple structure and can occur on the root tip in the thousands! They are basically an extension of the root’s external cells. They are very short-lived and are constantly being replaced.
Root hairs act like a sponge underground. They absorb nutrients and water which are sent through the tip of the plant’s root. The fact that there are so many root hairs on each root increases the amount of water and nutrients the plant can absorb from the soil.
Root hairs are an extension of the root. While the root is a complex multicellular organism, root hairs are very small, single-celled, and only extend out just a few millimeters from the root. Root hair cells are constantly dying off and being replaced through a cell division process called mitosis.Because root hairs are so small, they are also very delicate. If you have ever repotted a plant, you know that you need to do so very carefully and that you should minimize disturbance of the roots and the soil around them. With too little care, the root hair cells will be damaged and removed from the plant.
This makes it very difficult for the plant to get nutrition from the new soil.
Though they are small in structure, roots hairs have a very big job. Plants grow root hairs on the tips of their roots to increase surface area underground, which helps the plant absorb more water and nutrients. Root hairs do not provide any structural support because they are far too small, but they are an integral part of the root system of a plant.
Learn about root hairs in plants from this lesson and, thereafter, take the opportunity to:
- Define taproots and provide examples
- Illustrate the structure of root hairs
- Recognize the function and importance of root hairs