Explain why DNA replication is called semiconservative
The correct answer and explanation is:
Answer:
DNA replication is called semiconservative because each of the two daughter DNA molecules contains one original (parental) strand and one newly synthesized strand.
Explanation:
During DNA replication, the double helix structure of the DNA is unwound by the enzyme helicase. This separates the two strands of the original DNA molecule. Each strand serves as a template for the formation of a new complementary strand. DNA polymerase, the enzyme responsible for adding nucleotides, adds new nucleotides to the exposed bases of each original strand, following the base-pairing rules (adenine pairs with thymine, and cytosine pairs with guanine).
The term semiconservative refers to the fact that each new DNA molecule consists of one old (parental) strand and one new strand. This ensures that the genetic information is preserved while also allowing for the creation of an exact copy of the original DNA molecule. The process was first demonstrated by the Meselson-Stahl experiment in 1958, which provided experimental evidence supporting the semiconservative model.
Before replication, the DNA molecule consists of two strands that are complementary. After replication, each of the two daughter molecules will have one strand from the original DNA and one new strand. This method of replication helps minimize errors, as the original strand serves as a template to guide the correct sequence of nucleotides in the new strand.
The semiconservative nature of DNA replication is critical for maintaining the integrity of genetic information during cell division. By preserving half of the original DNA in each new molecule, it helps ensure the accurate transmission of genetic material from one generation of cells to the next. This method of replication is essential for the growth, repair, and maintenance of organisms.