Table of Contents
What is DNA replication carried out by?
DNA polymerases
DNA polymerase DNA polymerases are a family of enzymes that carry out all forms of DNA replication. DNA polymerases in general cannot initiate synthesis of new strands, but can only extend an existing DNA or RNA strand paired with a template strand.
What happens in DNA replication in order?
DNA replication steps. There are three main steps to DNA replication: initiation, elongation, and termination. In order to fit within a cell’s nucleus, DNA is packed into tightly coiled structures called chromatin, which loosens prior to replication, allowing the cell replication machinery to access the DNA strands.
What carries out the process of replication?
The helicase unzips the double-stranded DNA for replication, making a forked structure. The primase generates short strands of RNA that bind to the single-stranded DNA to initiate DNA synthesis by the DNA polymerase. This enzyme can work only in the 5′ to 3′ direction, so it replicates the leading strand continuously.
What is a replication sequence?
autonomous replication sequence (ARS) A segment of a DNA molecule necessary for the initiation of its replication; generally a site recognized and bound by the Proteins of the replication system.
What is an example of DNA replication?
When a cell divides, it is important that each daughter cell receives an identical copy of the DNA. This is accomplished by the process of DNA replication. For example, a strand of DNA with a nucleotide sequence of AGTCATGA will have a complementary strand with the sequence TCAGTACT (Figure 9.2.
How is the process of DNA replication carried out?
The process of DNA synthesis, in which the two original strands of the molecule separate, and each acts as a template on which a new complementary strand is laid down. DNA “copying” is carried out by a series of enzymes. These enzymes “unzip” a molecule of DNA.
What kind of enzyme is needed for DNA replication?
A DNA cutting enzyme that excises (removes) DNA, especially damaged DNA. The form of native DNA, referring to its two adjacent polynucleotide strands wound into a spiral shape. An enzyme that creates a short RNA primer for initiation of DNA replication. A nitrogen base found in DNA and RNA.
How does the lagging strand of DNA begin replication?
The lagging strand begins replication by binding with multiple primers. Each primer is only several bases apart. DNA polymerase then adds pieces of DNA, called Okazaki fragments, to the strand between primers.
How are DNA sequences used to make proteins?
To carry out these functions, DNA sequences must be converted into messages that can be used to produce proteins, which are the complex molecules that do most of the work in our bodies. Each DNA sequence that contains instructions to make a protein is known as a gene.