Roots are modified in some plants to perform functions beyond their primary role of anchoring and absorbing water and nutrients. These modifications enhance survival and adaptation in diverse environments.
Here's a breakdown of the reasons:
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Absorption and Transport: While this is the primary function of roots, certain modifications optimize this process in specific environments. For example, some plants develop specialized roots that can efficiently absorb water from arid soils.
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Support: Some plants require extra support, especially in unstable environments.
- Prop roots: These roots arise from branches and grow downwards into the soil, providing additional stability (e.g., Banyan tree).
- Stilt roots: These roots develop from the lower nodes of the stem and anchor the plant firmly to the ground (e.g., Sugarcane).
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Food Storage: In some plants, roots are modified to store food reserves.
- Fleshy roots: These roots become swollen with stored carbohydrates, providing energy for future growth (e.g., Sweet potato, Carrot).
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Respiration: Plants in waterlogged soils often face oxygen deficiency. Some roots are modified to facilitate gas exchange.
- Pneumatophores: These specialized roots grow upwards out of the water or mud to obtain oxygen from the atmosphere (e.g., Mangroves).
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Other Specialized Functions: Roots can also be modified for less common but crucial functions like:
- Parasitic roots (Haustoria): These roots penetrate the host plant and absorb nutrients (e.g., Dodder).
- Contractile roots: These roots pull the bulb or corm deeper into the soil to protect it from temperature fluctuations (e.g., Crocus).
| Modification | Function | Example |
|---|---|---|
| Prop roots | Support | Banyan tree |
| Stilt roots | Support | Sugarcane |
| Fleshy roots | Food Storage | Sweet potato |
| Pneumatophores | Respiration | Mangroves |
| Haustoria | Nutrient absorption | Dodder |
In summary, roots undergo modification to adapt to diverse environmental conditions and to efficiently perform essential functions such as support, food storage, and respiration, in addition to their primary roles of anchorage and nutrient/water absorption.
