what is the function of DNA polymerases?
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They build new copies of the genes (DNA) identical to the original so then the cell can split into two identical cells
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That's like asking "WHY does the sun shine?" or "WHY does the heart pump blood?"  (Really.  Think about it.  Can you answer those questions?  If so, then please add this to your question so we can understand what you mean by WHY.)\n\nScience can't offer an answer to this kind of WHY question.  We can understand the mechanisms involved (the sun shines because of nuclear fission ... what you're calling the HOW) or give an answer in terms of higher-level function (the heart pumps blood to keep the organism alive).  But we can't ask the sun or a heart WHY it does what it does.  Similarly we can explain the process of replication, and the function it serves to reproduction, but beyond that, science can't ask a DNA molecule WHY it does what it does.
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Post Replication Repair Mechanism - DNA Repair\n\nThe reconstruction of a continuous two-stranded DNA molecule without mismatch from a molecule which contained damaged regions.  The major repair mechanisms are excision repair, in which defective regions in one strand are excised and resynthesized using the complementary base pairing information in the intact strands; photo reactivation repair, in which the lethal and mutagen effects of ultraviolet light are eliminated; and post -replication repair, in which the primary lesions are not repaired, but the gaps in one daughter duplex are filled in by incorporation of portions of the other (undamaged) daughter duplex.  Excision repair and post-replication repair are sometimes referred to as "dark repair" because they do not require light.
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Okazaki fragments \n\nshort fragments of newly synthesised dNA strands produced during dNA replication. All the known dNA polymerases can only synthesis DNA in one direction, the 5' to 3' direction. however as the strands separate, replication forks will be moving along one parental strand in the 3' to 5' direction and 5' to 3' on the other parental strand. On the former, the leading strand, DNA can be synthesised continuously in the 5' to 3' direction. On the other, the lagging strand, dNA synthesis can only occur when a stretch of single stranded DNA has been exposed and proceeds in the direction opposite to the movement of the replication fork (still 5' to 3). It is thus discontinuous and the series of fragments are then covalently linked by ligases to give a continuous strand. Such fragments were first observed by okazaki using pulse labelling with radioactive thymidine. In eukaryotes, okazaki fragments are typically a few hundred nucleotides long, whereas in prokaryotes they may contain several thousands of nucleotides.
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Store genes on chromosome\n \nOrganize genes into chromosomes to allow cell division.\n\nTransport regulatory factors & gene products via nuclear pores \n\nProduce messages ( messenger Ribonucleic acid or mRNA) that code for proteins \n\nProduce ribosomes in the nucleolus \n\nOrganize the uncoiling of DNA to replicate  key genes\n\n\n\n...and it's nucleus (777 above)
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I think what you're looking for has to do with replication. Every time the cell goes through mitosis to divide, it has to make an exact copy of all the DNA in the cell, so that there are two complete copies, one for each daughter cell. The process of replication and division is the cell cycle.\n\nIn replication, a complex of enzymes copies the DNA by unzipping the double helix to expose the single strands. Someone else mentioned A-T C-G bair pairing and that is correct. The four subunits in DNA are the bases, and they are abbreviated A,T,C and G. Just by the shape of the molecules, A will connect with T and C with G pretty much always (though there are exceptions that are beyond the scope of a general explanation). \n\nSo in replication, enzymes pull the two strands of the double helix apart in short regions, pulling apart the A-T C-G bair pairing. It is energetically unfavorable to have a single strand of DNA exposed and not base paired. Free nucleotides in the cell will come in and form hydrogen bonds with the exposed template strand (it will happen on both strands), and then enzymes will connect the newly deposited bases with phosphodiester linkages to form a new DNA molecule. This forms a new strand of what is called duplex DNA, meaning it is a new double helix. The complementarity of the base pairs drives replication to produce an exact copy of each part of the genetic code. The error rate is very low, but errors can and do occur, and there is proofreading machinery to check for mistakes and excise and replace incorrect base pairs.\n\nPictures are helpful...in the second link, scroll down to see the replication bubble. A replication fork and a replication bubble are essentially the same thing...it's the site where the double helix is open and replication is occurring.
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Restriction enzymes are cutting enzymes found in bacteria. They cut within the DNA molecule and are called restriction endonucleases. They recognize a specific sequence 0f DNA nucleotides and cut the molecules there, producing sticky ends. A missing gene is then added. Another enzyme, DNA ligase, attaches back the DNA molecule. So, of course you end up with two DNA strands. The new DNA produced is known as recombinant DNA. This technology is used in human therapy. Some examples are: human insulin to treat diabetes type I and human factor VIII for the treatment of hemophilia.
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Transcription is the process of creating an RNA copy of one's DNA or mRNA.  RNA polymerase is responsible for this process.  This process is very important because mRNA is then used in "translation" to form proteins by means of a Ribosome.  \n\nYou need a TATA box for transcription.  There are three types of RNA polymerase: types 1, 2 and 3.  Type 3 RNA Polymerase typically are the ones with the TATA boxes.\n\nTake a look at this website to watch how RNA polymerase synthesizes a new mRNA through transcription:\nhttp://www.phschool.com/science/biology_place/biocoach/transcription/complete.html\n\nHave fun!
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A strand of DNA contains genes, areas that regulate genes, and areas that either have no function, or a function which we do not (yet) know: also see last bullet point in this section for the difference between DNA and RNA; \nDNA is organized as two complementary strands, head-to-toe, with bonds between them that can be "unzipped" like a zipper, separating the strands; \nDNA is a chain of chemical "building blocks", called "bases", of which there are four types: these can be abbreviated A, T, C, and G. Each base can only "pair up" with one single predetermined other base: A+T, T+A, C+G and G+C are the only possible combinations; that is, an "A" on one strand of double-stranded DNA will "mate" properly only with a "T" on the other, complementary strand; \nU occasionally replaces T, notably in PBS1 phage DNA; you can thus substitute "U" for "T" throughout this section. \nBecause each strand of DNA has a directionality, the sequence order does matter: A+T is not the same as T+A, just as C+G is not the same as G+C; \nFor each given base, there is just one possible complementary base, so naming the bases on the conventionally chosen side of the strand is enough to describe the entire double-strand sequence; \nThe genetic
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It does what any DNA does.  It controls protein synthesis via messenger RNA.
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The answer above is wrong- RNA polymerase is an enzyme involved in transcription. \n\nThe polymers made are:\n\nDNA in DNA replication\n\nRNA in DNA transcription
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Restriction Enzymes: \n\n \n\nThese are enzymes that cleave the strands of DNA at specific sites, according to the nucleotide sequence. They are counterparts of proteolytic enzymes such as trypsin, chymotrypsin in the world of nucleic acids. They are highly specific, and the sites they recognize may be very rare. Restriction enzymes are found in nature, primarily produced by bacteria as part of a defense system. \n\nThere are several types of restriction enzymes. We will focus on Type II, which is the type most widely used experimentally. \n\nNuclease: an enzyme that cleaves a nucleic acid\n\nRestriction Endonuclease: an enzyme that cleaves within a segment of nucleic acid, when it recognizes a specific sequences of bases. (Restriction enzyme)\n\nTypically, they are dimeric, and cleave at symmetrical sequences of DNA.\n\nExamples EcoR I and BamH I\n\n(See Chime link)\n\nHow do Restriction Enzymes recognize particular sequences of DNA?\n\nDo they open up the strands, in order to see the bases?\n\nNo, they bind along the major or minor grooves, and interact with the edges of the bases, for sequences specificity, \n\nand also with the sugars and the phosphates, for non-specific binding. This involves, H-bonding, hydrophobic contacts, and electrostatic interactions (ion pairs).
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Synthesis\nSynthesis of RNA is usually catalyzed by an enzyme, RNA polymerase, using DNA as a template. Initiation of synthesis begins with the binding of the enzyme to a promoter sequence in the DNA (usually found "upstream" of a gene). The DNA double helix is unwound by the helicase activity of the enzyme. The enzyme then progresses along the template strand in the 3’ -> 5’ direction, synthesizing a complementary RNA molecule with elongation occurring in the 5’ -> 3’ direction. The DNA sequence also dictates where termination of RNA synthesis will occur.
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An enzyme is a protein that catalyzes, or speeds up, a chemical reaction.\nEnzymes are essential to sustain life because most chemical reactions in biological cells would occur too slowly, or would lead to different products without enzymes\n\nLike all catalysts, enzymes work by providing an alternate pathway of lower activation energy of a reaction, thus allowing the reaction to proceed much faster. Enzymes may speed up reactions by a factor of many millions. An enzyme, like any catalyst, remains unaltered by the completed reaction and can therefore continue to function. Because enzymes do not affect the relative energy between the products and reagents, they do not affect equilibrium of a reaction.
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Well, some biological purposes of a phosphate group:\n\nAlternating phosphate groups and deoxyribose sugars form the backbone of DNA. To each sugar is attached a nitrogenous base.\n\nPhosphate groups can be removed from ATP (adenosine triphosphate), releasing a relatively large amount of energy, forming ADP and a Pi group.\n\nPhosphate groups are very negatively charged. Sometimes, cells add a phosphate group to glucose to keep it from passing through a cell's plasma membrane.\n\nAnd there are other uses..
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U meant for denaturing the DNA strands  Mainly verymuch important role playing in the   polymerization  chain reaction for amplifiaction of the DNA synthesis . When DNA get separated while in the melting temp .Forward and reverse primers  complimentary sequences will bind  to the DNA strands while in the annealing temp, it leads to the DNA synthesis.
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To ensure DNA is passed on correctly  the chromosmes tightly pack the DNA along with Histone proteins which basically protect it. During cell division when the cell  is divinding the proteins detach themselves fromthe DNA to allow for copying to take place. The copying is carried out by variious enzymes which many of which include those which acarry out proof reading  i.e error corrections. more specifically they prevent   wrong sequences from being copied. bear in mind in the human DNA is 3 Billion base paries long. so on average 2-3 nucleotides are mutations in each cell cycle. These generally go unoticed as they are silent mutations. The cell cycle is one of the most important reactions in any species and so naturally it has evolved to be as perfect as possible, hene it has a very high level of controll at every stage. sometimes these fail  hence it leads to things like cancers etc ..