DNA replication is the process of copying a double-stranded deoxyribonucleic acid (DNA) molecule, a process essential in all known life forms. The general mechanisms of DNA replication are different in prokaryotic and eukaryotic organisms.
DNA Replication
Before a cell can divide, it must duplicate all its DNA. In eukaryotes, this occurs during S phase of the cell cycle.
The Biochemical Reactions ...
DNA Replication
DNA replication is the process by which a molecule of DNA is duplicated. When a cell divides, it must first duplicate its genome so that each daughter cell winds up with a complete set of chromosomes.
Narration Transcription ...
DNA Replication.
During replication the DNA molecule unwinds, with each single strand becoming a template for synthesis of a new, complementary strand.
DNA replication: The use of existing DNA as a template for the synthesis of new DNA strands.
DNA sequence: The relative order of base pairs in any sample of DNA. See base sequence analysis.
DNA replication
The process by which the DNA double helix unwinds and makes an exact copy of itself. [Talking Glossary]
DNA sequencing ...
DNA replication precedes the start of meiosis I. During prophase I, homologous chromosomes pair and form synapses, a step unique to meiosis.
DNA replication
The process of making an identical copy of a section of duplex (double-stranded) DNA, using existing DNA as a template for the synthesis of new DNA strands. In humans and other eukaryotes, replication occurs in the cell nucleus.
DNA replication for the lagging strand is discontinuous and away from the replication fork. The small fragments synthesized are called Okazaki fragments and later stitched together by DNA Ligase.
Related ...
DNA replication occurs when a single-stranded chromosome produces a second chromatid.
Click here to review DNA synthesis (replication).
Overview of the Cell Cycle ...
DNA replication involves a great many building blocks, enzymes and a great deal of ATP energy (remember that after the S phase of the cell cycle cells have a G phase to regenerate energy for cell division).
In DNA replication, the lagging strand is the DNA strand at the opposite side of the replication fork from the leading strand. It goes from 5' to 3' (these numbers indicate the position of the molecule in respect to the carbon atoms it contains).
See DNA replication.
Thymine (T) A nitrogenous base, one member of the base pair A-T (adenine-thymine).
Transcription The synthesis of an RNA copy from a sequence of DNA (a gene); the first step in gene expression. Compare translation.
Errors in DNA replication can also lead to mutations. Certain gene products repair damage to chromosomes, thereby minimizing mutations in the cell.
Therefore DNA replication is both a ‘curse' and ‘bliss' for the epigenome, as it disrupts its stability by causing chromatin perturbations, ...
The smooth endoplasmic reticulum is the area in a cell where ___ are synthesized. a) polysaccharides; b) proteins; c) lipids; d) DNA
The mitochondrion functions in ____. a) lipid storage; b) protein synthesis; c) photosynthesis; d) DNA replication; ...
For example, most living things have evolved elaborate molecular machinery that checks for and corrects errors during the process of DNA replication, keeping their mutation rate down to acceptably low levels; conversely, ...
protein synthesis, DNA replication, glucose synthesis in plants) and catabolism, the degradation of molecules usually for the production of energy (e.g., glycolysis, Krebs Cycle).
A powerful method for amplifying specific DNA segments which exploits certain features of DNA replication. For instance replication requires a primer and specificity is determined by the sequence and size of the primer.
A unique dNA sequence of a replicon at which dNA replication is initiated and proceeds bidirectionally or unidirectionally.
A type of DNA replication where a replication fork moves around a circular DNA molecule, producing a single-stranded concatamer (much like the way toilet paper peels off the roll).
Origin of replication (ori ) Section of DNA sequence which is recognised by a cell's DNA replication proteins, allowing initiation of new DNA synthesis.
Due to polymerase slip (a.k.a. polymerase chatter), during DNA replication there is a slight chance these repeat sequences may become altered; copies of the repeat unit can be created or removed.
short DNA fragment found during discontinuous DNA replication
Source: Jenkins, John B. 1990. Human Genetics, 2nd Edition. New York: Harper & Row
...
A short sequence (of RNA or DNA) from which DNA replication can initiate. May be either a synthetic DNA or RNA or a length of RNA synthesized in vivo by primase.
DNA helicase - an enzyme that participates in DNA replication by unwinding the double helix near the replication fork
DNA ligase - fills in nicks and gaps made in polynucleotide strands ...
S-phase - second stage of interphase between G1 and G2; period of DNA replication.
sister chromatids - two identical copies of a parent chromosome which are attached to one another at the centromere.
(ly-gaze)
width="400" valign="TOP"
A linking enzyme essential for DNA replication; catalyzes the covalent bonding of the 3' end of a new DNA fragment to the 5' end of a growing chain.
DNA methylation ...
cell cycle, mitotic spindle, DNA replication, kinetochore, microtubule
Search the Web
Custom Search ...
polytene chromosome - large chromosome resulting from repeated DNA replication and alignment of homologs in the absence of mitosis; found in salivary glands and some other tissues of dipteran insects.
Replicon. A chromosomal region containing the DNA sequences necessary to initiate DNA replication processes.
Repressor. A DNA-binding protein in prokaryotes that blocks gene transcription by binding to the operator.
nucleus -- Membrane-bound organelle which contains the DNA in the form of chromosomes. It is the site of DNA replication, and the site of RNA synthesis.
Deletion A type of mutation in which one or more base pairs are left out in DNA replication; also, the absence of one or more bases from a nucleotide sequence in a gene.
Telomere
The ends of chromosomes. These specialized structures are involved in the replication and stability of linear DNA molecules. See DNA replication.
meiosis Process of cell division by which egg and sperm cells are formed, involving a diminution in the amount of genetic material. Comprises two successive nuclear divisions with only one round of DNA replication, ...
First, all the chromatin strands make copies of themselves through the process of DNA replication.
Interphase That portion of the cell cycle when the nuclear membranes have formed, the chromosomes have decondensed and the cell is going about its normal business. During this interval DNA replication takes place.
They extend the DNA using deoxyribonucleotide triphosphates (dNTP) as substrates and releasing pyrophosphates. The dNMPs are added to the 3' OH end of the growing strand (thus, DNA replication proceeds from 5' to 3' end).
 See also: Replication, DNA, Cells, Organ, Cell
|
