In semiconservative DNA replication, the process results in two DNA molecules. Which statement best describes the composition of each daughter DNA molecule after replication?

• A. One daughter molecule contains two original (parental) strands and the other contains two newly synthesized strands.
• B. Each daughter molecule contains one original (parental) strand and one newly synthesized strand.
• C. Each daughter molecule contains two entirely newly synthesized strands.
• D. Each daughter molecule contains strands made of alternating old and new DNA segments within the same strand.

Answer: (B)

Verified step by step guidance

1. Recall the definition of semiconservative DNA replication: during this process, each of the two original DNA strands serves as a template for the synthesis of a new complementary strand.
2. Understand that after replication, each daughter DNA molecule consists of one strand from the original (parental) DNA and one newly synthesized strand.
3. Recognize that this means the two daughter DNA molecules are identical to each other, each containing one old strand and one new strand.
4. Contrast this with other models of replication, such as conservative replication (where one molecule has both original strands and the other has both new strands) and dispersive replication (where strands are mixtures of old and new segments).
5. Conclude that the semiconservative model best fits the description: each daughter molecule contains one original (parental) strand and one newly synthesized strand.