Plant Reproduction: Pollination — Important Questions

Mustard

Step 1: Bisexual flowers contain both stamen (male organ) and pistil (female organ) in the same flower. Step 2: Mustard, rose, Hibiscus, and petunia are examples of bisexual flowers. Step 3: Papaya, corn, and cucumber have unisexual flowers — each flower has either only stamen or only pistil. Step 4: This is an important distinction because it affects how pollination happens — bisexual flowers can self-pollinate, while unisexual flowers often require cross-pollination. Step 5: Knowing which plants are bisexual vs unisexual helps us understand their reproduction strategy.

From the anther to the stigma of the same flower or another flower on the same plant

Step 1: Pollination always involves transfer of pollen from anther to stigma — this direction is fixed and cannot be reversed. Step 2: In self-pollination, ONLY ONE plant is involved — the pollen moves within the same flower OR to another flower on the very same plant. Step 3: This is why it is called 'self' pollination — the plant pollinates itself. Step 4: Cross-pollination is the opposite — it involves TWO different plants of the same species. Step 5: Option D describes cross-pollination, not self-pollination. Examples of self-pollinating plants are pea, orchid, and sunflower.

Pollen from one plant moves to the stigma of another plant of the same species.

Step 1: Cross-pollination always involves TWO different plants — this is the key difference from self-pollination. Step 2: Critically, the two plants must be of the SAME species — an apple tree's pollen goes to another apple tree's stigma, not a mango tree's stigma. Step 3: Cross-pollination going to a different species would not result in successful fertilization. Step 4: Pollen never moves from stigma back to anther — pollen always moves FROM anther TO stigma. Step 5: Cross-pollination leads to greater genetic diversity in offspring, making plants stronger and more varied.

Sticky pollen grains stick to the bee's body and get transferred to the stigma of the next flower it visits.

Step 1: Insect-pollinated flowers attract bees and butterflies using bright-coloured petals, sweet scent, and nectar. Step 2: When a bee enters the flower to drink nectar, its body brushes against the anthers. Step 3: The pollen grains, being sticky and large, cling to the bee's body (legs, abdomen, wings). Step 4: When the bee visits the next flower of the same kind, these pollen grains rub off onto the sticky stigma — completing pollination. Step 5: The bee does not eat and deposit pollen, and a bee's wings are too small to create sufficient wind for pollination — the direct body contact is