The process of copying a double-stranded DNA molecule to create two identical DNA molecules is called replication. One of the most fundamental processes that takes place in a cell is DNA replication. Every time a cell splits, the DNA, or genetic material, that the two daughter cells produce must match exactly that of the parent cell. Every strand of DNA that already exists serves as a template for replication in order to do this.
How is DNA replicated?
The opening of the double helix and separation of the DNA strands, priming of the template strand, and construction of the new DNA segment are the three main stages of replication. The origin is the precise place where the two strands of DNA uncoil upon separation. Subsequently, a number of proteins and enzymes cooperate to prime the strands for replication. Ultimately, the building of the new DNA strands is coordinated by a unique enzyme known as DNA polymerase. Although the three-stage process described below is generally applicable to all cells, depending on the type of organism and cell, there may be unique variances within the process.
How are DNA strands replicated
DNA polymerase wraps itself around the primer-attached single unwinding polynucleotide strand and adds additional nucleotides to the exposed nitrogenous bases. The polymerase builds a new DNA strand on top of the old one in this manner.
DNA polymerase builds the new strand by utilizing the pool of free-floating nucleotides surrounding the old strand as it moves down the unraveled DNA strand. The nucleotides that comprise the new strand are matched with partner nucleotides in the template strand; A and T nucleotides and C and G nucleotides always pair with each other due to their chemical shapes. Two complementary strands of DNA are produced as a result of this process, which is called complementary base pairing.
Base pairing guarantees that the nucleotide sequence in the template strand is precisely matched to the complementary sequence in the new strand, which is often referred to as the template strand's anti-sequence. The complementary strand of the newly created strand will eventually have the same sequence as the original template strand when it is replicated. Thus, the replication process proceeds as a series of sequence and anti-sequence copying that maintains the original DNA's coding due to complementary base pairing.
Enzymes associated with DNA replication:
Helicase - Unwinds two strands of DNA
Gyrase - Relieves the strain on DNA strands
RNA primase - Inserts an RNA primer on the strands of DNA
DNA polymerase III - Attaches to RNA primer, adds DNA nucleotides from 5' to 3' direction
DNA polymerase I - Removes RNA primer, inserts DNA nucleotides
DNA ligase - Joins Okazaki fragments together
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