Science (086) — AI-generated practice question

DNA in the nucleus acts as the blueprint for making proteins. Any error during DNA copying changes the genetic information, which causes different (abnormal) proteins to be made. Since proteins determine body design, even a small copying error can alter the physical characteristics of an offspring.

Such errors arise because biochemical copying reactions are not absolutely reliable. If the error is drastic, the new cell may die. If it is minor, it survives but the offspring shows a variation — a subtly different characteristic from its parent.

Source: Chapter 7, Section 7.1

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• The examiner wants you to trace the chain: DNA error → wrong protein → altered body design → changed characteristic.
• Mention both outcomes of an error: fatal (cell dies) and non-fatal (variation survives).
• Key phrase to include: "biochemical reactions are not absolutely reliable" — directly from the textbook.
• Avoid writing a long essay; 3 marks = 3 clear logical steps.