Pollination in Flowering Plants – Types, Agents & NEET Tricks

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🌼 Types of Pollination

Type Definition

Autogamy Pollen transfer within the same flower
Geitonogamy Transfer to another flower on the same plant
Xenogamy Transfer to a flower of a different plant


🧠 Trick to remember: “Auto = Same flower, Geito = Same plant, Xeno = Different plant”


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🌬️ Agents of Pollination

🔹 Abiotic Agents

Agent Adaptation

Wind (Anemophily) Small, dry pollen, feathery stigma (e.g., maize)
Water (Hydrophily) Light pollen, floating stigmas (e.g., Vallisneria)


🔸 Biotic Agents

Agent Example Adaptations

Insects Sunflower, Salvia Bright petals, nectar
Birds Hibiscus Tubular flowers
Bats Bauhinia Night blooming



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🌺 Features of Insect-Pollinated Flowers (Entomophily)

Brightly colored petals

Sweet fragrance

Nectar glands

Sticky pollen


🧠 Mnemonic: “Bright, Fragrant, Sticky, Sweet = Bug Treat”


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🌱 Outbreeding Devices in Plants

To prevent self-pollination and promote genetic diversity:

Dichogamy: Anther and stigma mature at different times

Herkogamy: Physical barrier between anther and stigma

Self-incompatibility: Genetic mechanism prevents fertilization



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🌿 Pollen-Pistil Interaction

Pollen germinates on stigma

Pollen tube grows toward ovule

Double fertilization occurs in angiosperms

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