Question

which statement best describes the dna molecules produced by dna replication?
a. each resulting dna molecule contains one original strand and one new strand.
b. the original dna molecule is separated into fragments by enzymes and then reassembled into a new sequence.
c. the original dna molecule is copied, and enzymes form an entirely new dna molecule.
d. each resulting dna molecule is made of two new strands, and the template molecule is discarded.

Explanation:

DNA replication follows the semi - conservative model. In this model, the double - stranded DNA unwinds, and each original strand serves as a template for the synthesis of a new complementary strand. So, each resulting DNA molecule has one original strand (from the parent DNA) and one newly synthesized strand.

• Option B is incorrect because DNA replication is not about fragmenting and reassembling the original DNA into a new sequence.
• Option C is incorrect as it is not an entirely new DNA molecule; it has one original strand.
• Option D is incorrect because the template strands are not discarded; they are part of the new DNA molecules.

Answer:

A. Each resulting DNA molecule contains one original strand and one new strand.