Why is DNA replication described as semi-conservative?
Answer and explanation
Correct answer: B. Each new DNA molecule keeps one original strand and gains one new strand
- Step 1: The two strands of the original molecule separate, and each acts as a template for a new complementary strand. Step 2. So each daughter molecule contains one old strand and one new strand. Answer: Each new DNA molecule keeps one original strand and gains one new strand. Why not the others: Two newly built strands would describe conservative replication, in which the original molecule stays whole. No part of the original DNA is broken down, and the whole genome, not half of it, is copied before cell division.
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