Question

___ unwinds the DNA structure and makes it lay flat

___ adds new nucleotides to each strand and a subunit proofreads the new nucleotides
___ seals the fragments into one long strand
___ makes a dent in the double helix and then begins to unzip it

Answer 1

DNA replication involves enzymes like helicase opening up the double helix, primase synthesizing RNA primers, DNA polymerase adding and proofreading nucleotides, and DNA ligase sealing the nucleotide fragments into a continuous strand.

Step-by-step explanation:

The student's question pertains to the process of DNA replication, which is a series of biological steps by which a cell duplicates its DNA. In this process:

1. Helicase unwinds the DNA structure and makes it lay flat, by opening up the DNA-forming replication forks.
2. DNA polymerase adds new nucleotides to each strand and a subunit proofreads the new nucleotides. It is the main enzyme that adds nucleotides in the 5'-3' direction and removes RNA primers to replace them with DNA.
3. DNA ligase seals the fragments into one long strand by forming phosphodiester bonds between the Okazaki fragments on the lagging strand.
4. Primase synthesizes RNA primers needed to start replication, effectively making a dent in the double helix before the helicase begins to unzip it.

Other proteins like single-strand binding proteins, topoisomerase, and the PCNA sliding clamp protein also play crucial roles in the stabilization and synthesis of the new DNA strands.