Biology
Grade-8
Easy
Question
Which term refers to a farmer choosing the best corn from this year to plant next year?
- Natural selection
- Selective breeding
- Genetic engineering
- None of the above
Hint:
The farmers kept the kernels from plants that had desirable traits and planted them for the harvest the following season. Artificial selection or selective breeding are terms used to describe this technique.
The correct answer is: Selective breeding
- When early Mexican farmers simply decided which kernels (seeds) to plant, they made the earliest domestication of maize. They discovered that not all plants were phenotypically equal.
- It's possible that some plants grew bigger than others, or that some kernels had greater flavors or were easier to crush.
- The farmers kept the kernels from plants that had desirable traits and planted them for the harvest the following season. Artificial selection or selective breeding are terms used to describe this technique.
- Over time, maize cobs grew bigger and had more rows of kernels, finally taking on the shape of modern maize.
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