Final answer:
The statement that a single replication fork in Theta replication proceeds around the entire circular DNA molecule to produce two complete circular DNA molecules, each consisting of one old and one new nucleotide strand, is true. DNA replication is semi-conservative, consistent across prokaryotes and eukaryotes.
Step-by-step explanation:
In Theta replication, if a single replication fork is present, it proceeds around the entire circular DNA molecule. This is a semiconservative process where each of the two strands that make up the double helix serves as a template for new strands to be copied, resulting in two complete circular DNA molecules. These molecules each consist of one old (parental) strand and one new (daughter) strand. Therefore, the statement is True.
During the process of DNA replication, multiple enzymes such as DNA polymerase and helicases are involved to ensure that each new DNA double helix has one original strand and one newly synthesized strand. The replication fork is essential for unwinding the DNA and allowing each strand to serve as a template. This semi-conservative nature of DNA replication ensures that each daughter cell receives an identical copy of the DNA.