Leaf Modifications in Plants by BHS aakash

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Leaves are primarily meant for photosynthesis, transpiration, and gaseous exchange, but in many plants they undergo modifications to perform special functions. These leaf modifications help plants adapt to their environment.


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1. Leaf Base Modifications

Structures: Pulvinus, Stipule, Leaf sheath

These are modified parts of the leaf base that provide support, protection, or flexibility.



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2. Petiole Modifications

In some plants, the petiole becomes photosynthetic, taking over the function of the lamina (leaf blade).

Example: Australian Acacia (here, the true leaf is reduced and the petiole is flattened and green).



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3. Other Leaf Modifications

(a) Leaf Tendrils

Slender, coiled structures that help in climbing and support.

Example: Pea plant (Pisum sativum) – here, leaf tendrils replace the leaflets.


(b) Fleshy Leaves

Leaves become thick and swollen to store food.

Examples: Onion, Garlic.


(c) Spines

Leaves are reduced to spines to reduce water loss and provide protection against herbivores.

Example: Cactus.



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Quick Recap (Leaf Modifications)

Leaf base: Pulvinus, Stipule, Leaf sheath.

Petiole: Photosynthetic in Australian Acacia.

Leaf tendril: Climbing (Pea plant).

Fleshy leaf: Storage (Onion, Garlic).

Spines: Protection & water conservation (Cactus).



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