Why is DNA replication considered semiconservative?

• A. Each daughter DNA molecule retains both original (parental) strands while new strands are discarded.
• B. Each daughter DNA molecule is composed entirely of newly synthesized DNA strands.
• C. Each daughter DNA molecule contains one original (parental) strand and one newly synthesized strand.
• D. DNA replication conserves the original DNA sequence by copying only the coding strand and not the template strand.

Answer: (C)

Verified step by step guidance

1. Understand the concept of DNA replication: DNA replication is the process by which a cell copies its entire DNA before cell division, ensuring each daughter cell receives a complete set of genetic information.
2. Recall the structure of DNA: DNA is double-stranded, with each strand complementary to the other, running in opposite directions (antiparallel).
3. Define semiconservative replication: In semiconservative replication, each of the two new DNA molecules contains one original (parental) strand and one newly synthesized strand.
4. Explain why it is called semiconservative: Because half of the original DNA molecule (one strand) is conserved in each daughter molecule, while the other half is newly made, the process conserves half of the original molecule in each copy.
5. Contrast with other models: This differs from conservative replication (where the original molecule remains intact and a completely new molecule is made) and dispersive replication (where parental and new DNA are interspersed in both strands).