What type of replication is DNA replication?

What type of replication is DNA replication?

• A. Semi-conservative replication
• B. Conservative replication
• C. Dispersive replication
• D. Random replication

Answer: (A)

DNA replication copies the genetic material by using each original strand as a template to build a new complementary strand. This results in two daughter DNA molecules, each containing one old strand and one newly synthesized strand. That pattern is called semi-conservative replication, and it’s supported by classic experiments that tracked how DNA strands separate and re-form after replication. Why this fits best: after one round of replication, each molecule has one parental strand paired with a new strand, exactly the structure semi-conservative replication predicts. In contrast, a conservative model would produce one double helix consisting entirely of old DNA and another entirely of new DNA, which isn’t what is observed. A dispersive model would yield mixtures of old and new DNA segments within each strand, not the clean one-old-one-new pattern seen experimentally. “Random replication” isn’t a recognized mechanism for DNA copying and wouldn’t explain how each new molecule reliably inherits an intact template strand. So the description that matches the evidence is semi-conservative replication.

DNA replication copies the genetic material by using each original strand as a template to build a new complementary strand. This results in two daughter DNA molecules, each containing one old strand and one newly synthesized strand. That pattern is called semi-conservative replication, and it’s supported by classic experiments that tracked how DNA strands separate and re-form after replication.

Why this fits best: after one round of replication, each molecule has one parental strand paired with a new strand, exactly the structure semi-conservative replication predicts. In contrast, a conservative model would produce one double helix consisting entirely of old DNA and another entirely of new DNA, which isn’t what is observed. A dispersive model would yield mixtures of old and new DNA segments within each strand, not the clean one-old-one-new pattern seen experimentally. “Random replication” isn’t a recognized mechanism for DNA copying and wouldn’t explain how each new molecule reliably inherits an intact template strand. So the description that matches the evidence is semi-conservative replication.