Modifications of Roots - ep1

Root modifications occur when plant roots change their form to perform extra tasks beyond their normal duties. While ordinary roots hold plants firmly to the soil and absorb water and minerals, modified roots adapt to serve other needs, such as storing food and providing mechanical support.

Basic functions and plant modifications

In the human body, each organ has a specific function, such as eyes that see. In the same way, plant parts have specific functions to keep the plant alive. Roots normally hold the plant firmly to the soil and absorb water and minerals from the ground. Sometimes, plant organs go beyond these basic needs and perform something extra. This process is called modification, and it can occur in a plant's leaves, stems, and roots.

Purposes of root modifications

A root modifies itself according to the particular needs of the plant. Root modifications fall into four main categories:

• Storage of foods
• Mechanical support
• Gaseous exchange
• Other vital functions

Shapes of food storage roots

Roots that store food can be differentiated from one another based on their physical shape:

• Fusiform roots, also called spindle-shaped roots, are thick and swollen in the middle and thin and tapered at both ends, as seen in a radish.
• Napiform roots, also called top-shaped roots, are round at the top and have a thread-like structure at the other end, as seen in a beetroot.
• Conical roots look like a cone because they are thick at the sides and smooth and tapered at the end, as seen in a carrot. A carrot is not a fruit, but an underground root modified for storing food.

Roots for mechanical support

In addition to storing food, roots modify themselves to provide mechanical support to the plant. Plant roots that adapt to provide physical support include three types:

• Prop roots
• Stilt roots
• Climbing roots