Here is the answer to Short segments of newly synthesized DNA are joined into a continuous strand by_____. You will find the correct answer and explanations below.
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Short segments of newly synthesized DNA are joined into a continuous strand by _____.
Short segments of newly synthesized DNA are joined into a continuous strand by what?
- DNA polymerase
- helicase
- single-strand binding protein
- ligase
- primase
- Below are the answer and explanations.
DNA Replication
DNA replication is the biological process by which two identical DNA molecules are produced from a single original DNA molecule by replication of the DNA duplex before cell division.
The result of DNA replication is that one double-strand becomes two identical double strands. DNA replication is accomplished successfully through a mechanism called semi-conserved replication.
DNA replication occurs in all organisms in which DNA is the genetic material, and is the basis of biological inheritance.
The process of DNA replication
DNA replication consists of three main phases: initiation, elongation, and termination. The process of prokaryotic DNA replication is briefly explained.
DNA replication begins at a specific location in the genome (the replication start point), i.e., the target site of the initiation protein.
DNA unstranding process DNA is not only double helix but also in superhelix state before replication, and the existence of superhelix state is a necessary structural state before unstranding, and there are some specific proteins involved in unstranding besides unstranding enzyme. Such as the Dna protein in E. coli, etc.
Once the DNA local double-stranded unraveling, there must be ssDNA protein to stabilize the unraveled single-stranded, to ensure that this local will not revert to double-stranded. The initiation process of the two single-stranded DNA replications differs. However, both the leading and trailing strands require an RNA primer to initiate the synthesis of the daughter strand DNA.
A variety of DNA polymerases play different roles in the DNA replication process. In E. coli, DNA Pol III is the polymerase primarily responsible for DNA replication. It assembles into a replication complex on the replication branch with a high degree of persistence, remaining intact throughout the replication cycle. In contrast, DNA Pol I is the enzyme responsible for replacing RNA primers with DNA.
In the vicinity of the replication fork, a ribosome-like size complex, called the DNA replisome, is formed with two sets of DNA polymerase III holoenzyme molecules, initiator and helix.
Eukaryotes begin DNA replication at multiple points on the chromosome. Thus replication forks meet and terminate at many points on the chromosome.
Because eukaryotes have linear chromosomes, DNA replication cannot reach the very ends of the chromosomes. Due to this problem, DNA at the ends of chromosomes is lost during each replication cycle. Telomeres are regions of repetitive DNA near the ends that help prevent gene loss. Telomere shortening is a normal process in somatic cells that shortens the telomeres of daughter DNA chromosomes.
As a result, cells can only divide a certain number of times before DNA loss prevents further division. In germ cells, telomerase extends the repetitive sequence of the telomere region to prevent degradation.
The termination of DNA replication occurs at a specific genetic locus, the replication termination site. The termination site sequence at this site is recognized and bound by a protein that prevents DNA replication bound to this sequence, preventing the replication fork from advancing and replication is terminated. The DNA replication end site binding protein of bacterial matter is also known as Ter protein.
Characteristics of DNA replication
- Semi-conserved replication.
When DNA is replicated, every single strand of parental DNA is used as a template to synthesize two identical double-stranded daughter DNAs, each of which contains one parental DNA strand. This phenomenon is called the semi-conserved replication of DNA.
When DNA is replicated, it needs to start at a specific site, which is a fragment with a specific nucleotide sequence, i.e. the replication site (replicon). In prokaryotes, the replication start site is usually one, while in eukaryotes it is multiple.
- Bidirectional replication
DNA replicates in two directions, with the replication initiation site as the center. However, in lower organisms, unidirectional replication can also occur.
- Semi-discontinuous replication
Since DNA polymerase can only polymerize the daughter DNA strands in the 5’→3′ direction, the two parental DNA strands are different when used as templates to polymerize the daughter DNA strands.
Correct Answer
This is the correct answer to Short segments of newly synthesized DNA are joined into a continuous strand by _____.
- D. ligase
Short segments of newly synthesized DNA are joined into a continuous strand by ligase.
Related questions:
- To create a molecule of recombinant DNA, which of the following is cut with a restriction enzyme?
- After DNA replication is completed, _____.
- What provides the energy for the polymerization reactions in DNA synthesis?
- All of the following are true about the DNA molecule, except__?
- Which type of DNA mutation involves the insertion of extra base pairs into the sequence?
