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The eukaryotic chromosomes are larger in size. Hence in order to overcome the limitation of DNA synthesis, multiple origins of replication are present in order to complete replication in a reasonable period of time.
- At the replication origin the strands of DNA must dissociate and unwind in order to allow access to DNA polymerase.
- Unwinding of the duplex at the origin as well as along the strands as the replication process proceeds is carried out by helicases.
- The resultant regions of single-stranded DNA are stabilized by the binding of single-strand binding proteins.
- The stabilized single-stranded regions are then accessible to the activities of other enzymes required for replication to proceed.
- The site of the unwound template strands is termed the replication fork.
In order for DNA polymerases to synthesize DNA they must encounter a free 3'-OH which is the substrate for attachment of the 5'-phosphate of the incoming nucleotide.
During replication the 3'-OH is supplied through the use of an RNA primer, synthesized by the primase activity. The primase utilizes the DNA strands as templates and synthesizes a short stretch of RNA generating a primer for DNA polymerase.
Synthesis of DNA proceeds in the 5'---->3' direction through the attachment of the 5'-phosphate of an incoming deoxy nucleosidetriphosphate (dNTP) to the existing 3'-OH in the elongating DNA strands with the concomitant release of pyrophosphate.
Initiation of synthesis, at origins of replication, occurs simultaneously on both strands of DNA.
DNA synthesis process then proceeds bidirectionally, with one strand in each direction being copied continuously and one strand in each direction being copied discontinuously.
The experimental support for this bidirectional mode of replication in the cells of higher eukaryotes was acquired by the fiber autoradiography of labeled DNAs got from mammalian cell cultures. When the replicating DNA extracted and isolated from eukaryotic cells are examined under the electron microscope, the clear "bubble" like structures extending from multiple replication origins are clearly visible.
source: www.examville.com
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What is used as a template for replication?
The DNA molecule itself serves as a template for replication. During DNA replication, the two strands of the double helix separate, and each strand serves as a template for the synthesis of a new complementary strand, resulting in the formation of two identical DNA molecules.
Semiconservative replication involes a template what is the template?
The template for semiconservative replication is the original DNA strand that serves as a guide for creating a new complementary strand. During DNA replication, each original parental strand acts as a template for the synthesis of a new daughter strand.
Is it DNA Copying or DNA Replication?
DNA copying and DNA replication are interchangeable terms that refer to the process of making an exact copy of a DNA molecule. During this process, the double-stranded DNA unwinds, and each strand serves as a template for the synthesis of a new complementary strand.
What is the term for the DNA strand that acts as a pattern to the newly synthesized DNA?
The DNA strand that acts as a pattern for the newly synthesized DNA is called the template strand. It serves as a guide during DNA replication, where complementary nucleotides are added to create a new DNA strand.
What form of DNA is used in replication?
In DNA replication, the double-stranded DNA molecule serves as a template for the creation of a new complementary strand. The process involves breaking the hydrogen bonds between the two strands and using each strand as a template for the synthesis of a new complementary strand.
What is used as a template for replication?
The DNA molecule itself serves as a template for replication. During DNA replication, the two strands of the double helix separate, and each strand serves as a template for the synthesis of a new complementary strand, resulting in the formation of two identical DNA molecules.
Semiconservative replication involes a template what is the template?
The template for semiconservative replication is the original DNA strand that serves as a guide for creating a new complementary strand. During DNA replication, each original parental strand acts as a template for the synthesis of a new daughter strand.
What is the role of the leading strand in DNA replication?
The leading strand in DNA replication serves as a template for the continuous synthesis of a new complementary strand of DNA. It is replicated in a continuous manner by DNA polymerase, allowing for efficient and accurate replication of the entire DNA molecule.
Is it DNA Copying or DNA Replication?
DNA copying and DNA replication are interchangeable terms that refer to the process of making an exact copy of a DNA molecule. During this process, the double-stranded DNA unwinds, and each strand serves as a template for the synthesis of a new complementary strand.
What is the process in which the DNA double helix unfold and each strand serves as a template for the synthesis of a new strand?
The process is called DNA replication. It begins with the unwinding of the DNA double helix by an enzyme called helicase. Each separated strand then serves as a template for the synthesis of a new complementary strand by DNA polymerase.
What acts as the origianl template in DNA replication?
A strand of DNA
In what direction does DNA replication occur from 5' to 3' on the template strand?
Yes, DNA replication occurs in the 5' to 3' direction on the template strand.
What is the term for the DNA strand that acts as a pattern to the newly synthesized DNA?
The DNA strand that acts as a pattern for the newly synthesized DNA is called the template strand. It serves as a guide during DNA replication, where complementary nucleotides are added to create a new DNA strand.
What form of DNA is used in replication?
In DNA replication, the double-stranded DNA molecule serves as a template for the creation of a new complementary strand. The process involves breaking the hydrogen bonds between the two strands and using each strand as a template for the synthesis of a new complementary strand.
DNA undergoes a process called when it is duplicated?
DNA replication
What is the significance of the reverse strand in DNA replication and transcription processes?
The reverse strand in DNA replication and transcription processes serves as a template for creating a complementary strand of RNA or DNA. This allows for accurate copying of genetic information and ensures proper functioning of cells.
How is retrovirus different from DNA virus?
Retro virus has reverse transcription in its replication cycle. In other words, rna is template for synthesis of dna. With dna virus, there is no reverse transcription in the replication cycle. Dna is the template for dna synthesis.
