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Science — CBSE Class 10 board question

Q1. [2]
"Variation is useful for the survival of species over time." Explain this statement with the help of an example.
Previously asked in CBSE board exam
2026 31/2/1 Q11
Generated by claude-sonnet-4-6 · 2026-06-15 06:51 · grounding rag
Model Answer

Variation means subtle differences among individuals of a species. When the environment changes drastically, most individuals may die, but variants better suited to the new conditions survive and reproduce.

Example: A population of bacteria lives in temperate water. Due to global warming, water temperature rises. Most bacteria die, but heat-resistant variants survive and multiply, ensuring the species continues.

Thus, variation is useful for survival of a species over time.

Source: Chapter 7, Section 7.1.1 – The Importance of Variation

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Explanation
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