Why is DNA replication described as 'semi-conservative'?

• A. DNA replication results in two completely new DNA molecules.
• B. DNA replication occurs only in one direction along the DNA strand.
• C. Each new DNA molecule is identical to the original DNA molecule.
• D. Each new DNA molecule consists of one original strand and one new strand.

Answer: (D)

Verified step by step guidance

1. Understand the concept of DNA replication: DNA replication is the process by which a cell duplicates its DNA, creating two identical copies from one original DNA molecule.
2. Learn about the term 'semi-conservative': In the context of DNA replication, 'semi-conservative' means that each of the two new DNA molecules contains one strand from the original DNA molecule and one newly synthesized strand.
3. Visualize the replication process: During replication, the double helix of the original DNA molecule unwinds, and each strand serves as a template for the formation of a new complementary strand.
4. Recognize the role of enzymes: Enzymes like DNA polymerase facilitate the addition of nucleotides to the growing new strand, ensuring that each new DNA molecule has one original and one new strand.
5. Conclude with the outcome: The semi-conservative nature of DNA replication ensures genetic consistency, as each new DNA molecule retains one of the original strands, preserving the genetic information.