BlogNEETImportant Topic of Biology: DNA replication

Important Topic of Biology: DNA replication

    Fill Out the Form for Expert Academic Guidance!


    Live ClassesBooksTest SeriesSelf Learning

    Verify OTP Code (required)

    I agree to the terms and conditions and privacy policy.


    DNA replicates semi-conservatives and is aided by a series of enzymes. Let us consider the process of DNA replication with the enzymes that play a role.

    DNA Replication is the natural process of producing two identical copies of DNA from a single unique molecule of DNA. The most important element of a biological heritage is DNA replication, which includes all living things. This is necessary for the division of cells during the formation and repair of damaged tissue and for ensuring that each new cell has its own copy of DNA.

    The parent’s DNA stays together and the newly formed daughter’s strands sit together in successive repetitions. Each of the two strands of parental DNA serves as a blueprint for the synthesis of new DNA in a semi-conservative manner; After replication, each discarded DNA is composed of one parent line or “old” thread and one “new” strand.

    Stages of DNA replication

    Here is a breakdown of DNA Replication:

    • Initiation

    DNA formation begins in certain areas near the DNA strand, called ‘origins,’ which are found within the replication complex. DNA helicase is an enzyme that releases a double-helical structure and produces each of the two strands to be used as reproductive templates. Hydrolyzing is a method used. ATP is used to disrupt connections that hold two strands together by forming bonds between nitrogen bases.

    Another enzyme involved in DNA replication is DNA Primase. It produces a small RNA primer that acts as a kick-starter for the DNA polymerase enzyme. The enzyme DNA polymerase is fully responsible for the formation and development of new strands of DNA-specific regions.

    • Stretching

    DNA polymerase can initiate the synthesis of new DNA to match the templates when it is connected to the original and dismantled the two strands of parental DNA (i.e., the strands of the template). It is noteworthy that DNA polymerase can only extend the primer by adding free nucleotides at the end of 3, not at the end of 5. During replication, RNA primers were added to the newly opened bases on the sleeping strand and DNA synthesis occurred in pieces but in 5 ‘to 3’ in the same manner as before. Okazaki pieces are the name of these pieces.

    • Termination

    The process of stretching new strands of DNA continues until the DNA template is no longer available for duplication (i.e., at the end of a chromosome) or a combination of two forks. The junction of the two repetitive forks is uncontrollable and occurs randomly throughout the chromosome length.

    After the DNA synthesis is completed, the newly produced strings should be tied and stabilized. Two enzymes are needed to achieve this stable phase in the lying strand. The RNAse enzyme removes the RNA primer from the beginning of each Okazaki episode and the DNA Ligase enzyme binds to the fragments to form a complete fiber.

    The role of enzymes in DNA Replication

    The process of DNA replication is highly dependent on enzymes. Many enzymes are involved in DNA replication, including DNA-based DNA polymerase, helicase, ligase etc. The main enzyme among them is DNA-based polymerase.

    • DNA-based polymerase

    With the help of other enzymes, it aids in polymerization, catalyzing, and regulating the entire process of DNA replication. The replication process uses deoxyribonucleoside triphosphates as both a substrate and a source of energy. There are three types of DNA polymerase:

    • DNA Polymerase I

    DNA repair protein. It participates in three different activities:

    The function of 5′-3 ′ polymerase
    5′-3 ′ exonuclease function
    3′-5 ′ exonuclease function

    • DNA Polymerase II

    The initial expansion and debugging are your responsibilities.

    • DNA Polymerase III

    Contains in-vivo DNA replication.

    Enzymes are used in the replication

    • Helicase
      Helicase is an enzyme that breaks down hydrogen bonds between DNA strands to unlock them. As a result, it contributes to the formation of a multiplication fork.
    • Ligase
      Ligase helps to bind broken DNA strands.
    • Primase
      This enzyme helps to produce RNA primers that are compatible with the DNA template strand.
    • Endonucleases
      In a DNA molecule, this causes one or two strands to be cut.

    The process of DNA replication in prokaryotes

    In prokaryotes, DNA replication occurs in the following areas:

    At the origin of reproduction, two strands of DNA are loosened.

    Helicase unlocks DNA, forming fork forks.

    Proteins bind to a single strand that encapsulates the DNA alongside a replica fork to prevent it from deteriorating.

    Topoisomerase blocks DNA from binding.

    • Primase is an enzyme that makes RNA primers. The DNA strand is related to these elements.
    • By the end of the primers, DNA polymerase III begins to add nucleotides.
    • Both the leading and next strands grow.
    • After removing the primers, the gaps are filled with DNA Polymerase I; ligase is used to close them.

    The process of DNA replication in eukaryotes

    DNA replication in eukaryotes is compared to that of prokaryotes. However, the initiation process in eukaryotes is much more complicated than prokaryotes. Many sources of replication can be found in eukaryotes. Some early proteins form a complex replica of the past. Although the process is similar, the enzymes used are not the same. The polymerization process in eukaryotes is made by the enzyme Pol I, and in prokaryotes, it is made by DNA Pol III.

    Also read: Structure of DNA and RNA


    What are two reasons why both strands of DNA could not be copied at the time of DNA writing?

    When both RNA codes are RNA codecs, two different RNA molecules are produced and two different proteins, making the genetic material more complex. Because the two RNA molecules interact, they will come together to produce dsRNA without translation, rendering the transcription process irrelevant.

    What is DNA fingerprinting and how does it work?

    DNA fingerprinting, also known as DNA typing, is a way of determining the nucleotide sequence of specific DNA fragments (VNTRs) that are unique to each individual. Each person has a unique set of DNA fingerprints. DNA fingerprints are the same for all cells, tissues, and human organs, unlike traditional fingerprints, which are only visible on the fingers and can be replaced with surgery.

    Chat on WhatsApp Call Infinity Learn

      Talk to our academic expert!


      Live ClassesBooksTest SeriesSelf Learning

      Verify OTP Code (required)

      I agree to the terms and conditions and privacy policy.