Lesson 1 ·Class 9 · Pollination and Fertilization · Sort Lab
Self-Pollination vs Cross-Pollination
The same act, two very different consequences.
Sort each statement into the kind of pollination it describes.
Sorted 0/10
All items sorted — check each bin.
VS
Free play — sort every item into the bin it belongs in; each correct drop tells you why. Switch to when you're ready to test yourself.
Self-pollination is reliable but produces no variation. Cross-pollination is wasteful but produces variation — and variation is what evolution needs.
What this lesson covers
Challenges to clear
- Fill the Self-pollination column correctly.
- Sort every statement.
- Fill the Cross-pollination column — pollen that must travel to another plant.
The task
Sort each statement into the kind of pollination it describes.
What this lesson covers
- Self-pollination — Autogamy: Pollen reaches the stigma of the same flower or plant (No second plant is involved at all.); Pollination is almost certain to succeed (Nothing has to travel, so nothing can go wrong.); Needs no external agent (Which is why it works even when pollinators are scarce.); Keeps the parental characters pure over generations (Useful to a breeder, but it also preserves any weakness.); Repeated over generations it weakens the race (Harmful recessive traits accumulate — inbreeding depression.)
- Cross-pollination — Allogamy: Pollen is carried to a different plant of the same species (Two parents contribute, so the offspring are genetically mixed.); Enormous quantities of pollen are wasted (Most wind-blown pollen never reaches a stigma.); Depends on wind, water or an animal (The plant must invest in nectar, scent or huge pollen output.); Produces variation, and stronger, more adaptable offspring (New combinations are the raw material of evolution.); Helps the species adapt to a changing environment (Variation means some offspring may cope with new conditions.)
Hint
Self-pollination is reliable but produces no variation. Cross-pollination is wasteful but produces variation — and variation is what evolution needs.