Final answer:
DNA replication is semi-conservative, meaning each new DNA molecule consists of one old (parental) strand and one new strand. The Meselson and Stahl experiment confirmed this model.
Step-by-step explanation:
The student's statement about DNA replication being conservative is inaccurate. In reality, DNA replication is semi-conservative, not conservative. In the semi-conservative process, each of the newly formed double helices has one strand from the parent DNA and one new strand.
During the replication process, the DNA double helix unwinds and each single strand serves as a template for the formation of a new complementary strand. This means that each of the two daughter DNA molecules contains one old (parental) strand and one new strand. This method ensures that each new molecule of DNA is an exact copy of the original, with the same sequence of nucleotides.
The Meselson and Stahl experiment provided pivotal proof supporting the semi-conservative model of DNA replication. Their results showed that after DNA replication, each new DNA molecule consisted of one strand from the original DNA and one newly synthesized strand.