some teacher out there needs to answer this now
Watson and Crick developed a model for the secondary structure of DNA in 1953. DNA is a long linear polymer that has two major components: a backbone made up of sugar and phosphate groups and a series of nitrogenous bases that project from the backbone. These two long strands twist around each other and certain of the nitrogenous bases pair inside the spiral forming a double helix molecule. The structure is stabilized by hydrogen bonds that form between the bases called adenine and thymine and the bases guanine and cytosine. Watson and Crick suggested that the A-T and C-G pairing rules suggested a way for DNA to be copied prior to mitosis or meiosis. They suggested that the existing strands of DNA served as a template for the production of new strands, with bases being added to the new strands according to complimentary base-pairing rules. Each existing or old strand separated and served as a template for the synthesis of a new second strand so that each daughter DNA molecule consists of one old strand and one new strand, This is called semi-conservative replication and though other hypotheses were proposed experiments proved this hypothesis.
DNA Replication Summary1. Helicase separates antipolar strands forming a replication fork.
2. Binding proteins keep strands separate and topoisomerase relieves tension and removes kinks to allow the double helix molecule to continue to unravel.
3. Primase adds an RNA primer with an OH group to chemically bond with the first dNTP.
4. Polymerase III (Pol I-IV) synthesizes the leading strand in the 5'-3' direction. Antipolar lagging strand primer synthesizes RNA primer.
5. Pol III elongates primer; produces Okazaki fragment
6. Pol I excises RNA primer and fills the gap.
7. DNA Ligase links Okazaki fragments to form a continuos strand.
8. DNA Polymerase III can proofread.
The double helix of the DNA unwinds. Then, the enzyme helicase 'unzips' the DNA by breaking the hydrogen bonds. Then, the enzyme DNA Polymerase pairs each of the two strands with the correct nitrogenous bases. The top strand is called the 'leading strand' and the bottom strand is called the 'lagging strand.' Then the enzyme ligase glues together the different fragments of the lagging strand of DNA. Now we have two exact replications of DNA, each with 46 chromosomes called daughter cells.
Process by which a cell duplicates its DNA before it divides.
DNA replication occurs due to an enzyme. The DNA unzips, and the enzyme pieces together new parts to make each half its own full DNA strand.
First, the double helix unwinds. Secondly, nucleotides then correctly create a strand. Third, the new strand seals up.
The three main steps in the process of DNA replication are initiation, elongation and termination. Initiation is the beginning of the process. During elongation new DNA strands are formed and in termination replication ends.
replication
DNA replication produces two copies of the DNA.
DNA replication
DNA replication produces a copy of the DNA. At the same time the cell in which the DNA is to be found splits into two with a copy of the DNA in each. DNA replication is caused by cell replication during the process of mitosis.
The three main steps in the process of DNA replication are initiation, elongation and termination. Initiation is the beginning of the process. During elongation new DNA strands are formed and in termination replication ends.
Replication.
DNA replication begins in areas of DNA molecules are called origins of replication.
The eight steps of DNA replication are: 1. DNA strands separate, 2. formation of replication fork, 3. RNA primase binds, 4. bases pair up, 5. elongation, 6. RNA primers removed, 7.termination, 8. repair. this can occur in any cell.
replication
Inhibitors of DNA replication are bacteria or toxins that inhibit the replication of DNA. E-Coli is an example of an inhibitor of DNA replication.
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.
DNA replication produces two copies of the DNA.
DNA replication
DNA replication produces a copy of the DNA. At the same time the cell in which the DNA is to be found splits into two with a copy of the DNA in each. DNA replication is caused by cell replication during the process of mitosis.
DNA replication occurs in living cells. The name of the sites where DNA replication occurs is called the origins of replication.
Transcription.