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Summarize the steps that occur in the process of chromosomal DNA replication. Please place the following steps in the proper order.

A. DnaA proteins bind to the origin of replication, resulting in the separation of the AT-rich region.
B. DNA helicase breaks the hydrogen bonds between the DNA strands, topoisomerases alleviate positive supercoiling, and single-strand binding proteins hold the parental strands apart.
C. Topoisomerases unravel the intertwined chromosomes, if necessary.
D. Primase synthesizes one RNA primer in the leading strand and many RNA primers in the lagging strand, and DNA polymerase III synthesizes the daughter strands of DNA.
E. DNA polymerase I removes the RNA primers and fills in that region with DNA, and DNA ligase covalently links Okazaki fragments together.
F. Replication continues until the two replication forks meet on the other side of the circular bacterial chromosome.

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Answer:

The proper order is:

A. DnaA proteins bind to the origin of replication, resulting in the separation of the AT-rich region.

B. DNA helicase breaks the hydrogen bonds between the DNA strands, topoisomerases alleviate positive supercoiling, and single-strand binding proteins hold the parental strands apart.

C. Topoisomerases unravel the intertwined chromosomes, if necessary.

D. Primase synthesizes one RNA primer in the leading strand and many RNA primers in the lagging strand, and DNA polymerase III synthesizes the daughter strands of DNA.

E. DNA polymerase I removes the RNA primers and fills in that region with DNA, and DNA ligase covalently links Okazaki fragments together.

F. Replication continues until the two replication forks meet on the other side of the circular bacterial chromosome.

Step-by-step explanation:

The process of DNA replication in prokaryotes starts at a point called ORIGIN OF REPLICATION. This site is where certain proteins recognize and bind to in order to kickstart the replication process. The following are orderly processes of DNA replication.

- DnaA proteins bind to the origin of replication, resulting in the separation of the AT-rich region.

- DNA helicase breaks the hydrogen bonds between the DNA strands to form two replication forks, topoisomerases prevent supercoiling of these separated DNA, and single-strand binding proteins hold the parental single strands apart, hence, making sure that they do not rewind again.

- In case DNA rewinds, topoisomerases unravel or disentangles the intertwined chromosomes, if necessary.

- DNA Primase synthesizes one RNA primer in the leading strand and many RNA primers in the lagging strand,which allows DNA polymerase III synthesize the daughter strands of DNA. Note that the synthesis of nucleotides on threading strand is continuous while nucleotides are synthesized in small fragments called OKAZAKI FRAGMENTS, on the lagging strand.

- DNA polymerase I removes the RNA primers and replaces with synthesized DNA in that region, and DNA ligase covalently links the Okazaki fragments (small fragments of DNA) together.

- Replication continues until the two replication forks meet on the other side of the circular bacterial chromosome.

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