Why is DNA replication described as semiconservative?

• A. Each daughter DNA molecule contains two entirely new strands with no parental DNA present.
• B. Replication conserves the original nucleotide sequence by preventing mutations during DNA synthesis.
• C. Each daughter DNA molecule contains two original (parental) strands that remain paired after replication.
• D. Each daughter DNA molecule contains one original (parental) strand and one newly synthesized strand.

Answer: (D)

Verified step by step guidance

1. Understand the term 'semiconservative' in the context of DNA replication. It refers to the way the DNA molecule is copied during cell division.
2. Recall that DNA is double-stranded, with each strand serving as a template for the formation of a new complementary strand.
3. During replication, the two strands of the original DNA molecule separate, and each original (parental) strand pairs with a newly synthesized strand.
4. This results in two daughter DNA molecules, each containing one original strand and one new strand, hence the term 'semiconservative' because half of the original molecule is conserved in each daughter molecule.
5. Contrast this with other possible models like conservative replication (where the original molecule remains intact and a completely new molecule is made) or dispersive replication (where parental and new DNA are interspersed in both strands), which are not how DNA replication actually occurs.