what holds the DNA double helix together???
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Consider a regular climbing ladder.  If the ladder was sawed in half by sawing each rung crosscut thru the middle than each half of the ladder would represent one  DNA strand.  Each new organism receives a single strand from each of it's parents.  The two strands join to make the new organism's double stranded DNA.  The rail or sides of the ladder would represent the sugar and phosphate link backbone of the DNA.  The sawed rung would represent the nucleic acid bases.  The bases are classified as either purines or pyrimidines.  The two purines are Adenine (A) and Guanine (G) which are similiar to the compound Purine.  The two pyrimidine bases are Thymine (T) and Cytosine (C) which are structured similiar to the compound Pyrimidine.  In RNA Thymidine is replaced by Uracil.  The collective term for these structures is "nitrogenous base".  Each base contains either/or hydrogen (h), nitrogen (n) and oxygen (o) atoms located on the structure where the "cut" would exhist on the sawed ladder rungs.  When these bases move close together there is an attraction between these atoms and a bridge forms called a hydrogen bond  or h-bond.Thymine has an o and a h.  Adenine has a h which is attracted to T's o and an n which is attracted to T' h. A and T always h-bond or pair.  Cytosine has an h,n,and o.  Guanine has two h's and an o.  one h on guanine is attracted to the o on cytosine, the other to the n.  The o is attracted to the h on cytosine.  Therefore C always pairs with G and is held together by three h-bonds, where A and T are paired by two h-bonds.  In total the h-bonds strongly bind the two DNA single strands together but one at a time they can be broken to seperate the strands much like a zipper opening link by link.  Since C always pairs with G their proportion is is always the same.  The same is true for A and T.  Each Dna single strand has what is called a 3' (three prime hydroxyl) and a 5' (five prime phosphate) end.  When the two single strands pair to form thd Double strand they Form with the 3' end of one strand joining at the 5' end of the other strand.  This is known as antiparallel since they are running in opposite directions.
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In DNA, the bases always appear in complimentary pairs - a DNA molecule is a double-strand of bases.  In this case, each C has a G stuck to it, so the # of each type will be the same.\n\nRNA is a single stranded molecule, so there are no matched pairs and there is no reason for the amount of any two bases to match.
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Units of information in DNA are stored as hydrogen bonds linking base pairs of amino acids including thymine, cytosine, adenine and guanine.  Each base can only be linked to a single complementary base, for example, A+T, T+A, C+G or G+C.  The order, or polarity, of each base pairing is important (meaningful) in this context.  Genetic information is determined by the sequence of base pairs forming a three-dimensional chain described as a double-helix.
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Usual,DNA is double helix (A form).DNA form include: A form, B form,....,Z form.DNA structure :\n base\n phosphast                 -----> nu ---->DNA\n sugar(desoxyrybonucleic)\n You can look at Nobelprizes.org
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According to the watson and crick model the DNA\nStucture is built like a spiral staircase .\nFr the rest of it try th link below.
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DNA is a molecule, not a living object. It can stay there as long as it is not disturbed and swept away.
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Well, there are quite a few ways. You could look and see that DNA has A bonded to  T and G bonded to C (which you could look up their exact make-up to discern them from other compounds, they are just simple nucleotides which form a chain to create what we call DNA). \n\nYou could tell by how their subunits are connected. DNA will have repetitive phosphodiester linkages (bonds between a  phosphate of one nucleotide and a carbon of another) which hold it together. Proteins on the other hand will have peptide linkages (bonds between a carboxyl group of an amino acid to an amino group of another; amino acids are much like nucleotides in DNA, they form chains to create proteins). \n\nDNA will be in a double helix, while proteins will be in all sorts of conformations (which is where they get their uses). \n\nSince proteins are just chains of amino acids you could recognize the specific amino acids on proteins (there are only 21 and all of their structures are known. note:*Ohio State University claims to have found a 22nd* ), thus making the substance a protein and not DNA since DNA has no amino acids in it. \n\nBut assuming  you could only look at the atoms like your question states and not how or what they they are connected to, you could still discern DNA from protein. DNA has phosphate since nucleotides (the things that make up DNA) are composed of a nitrogenous base, a deoxyribose sugar, and a phosphate group, while proteins have amino acids (none of which have phosphates) connected by carbons and nitrogens. So if for some reason you have the known number of atoms in two substances, but didn't known how they were connected and you were asked which one is the protein and which one is the DNA sequence. You would conclude that the one with the phosphate is indeed the DNA.
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DNA stands for DEOXYRIBONUCLEIC ACID.\nITs one of the type of Nucelic acid.In order to understand the role of DNA its important to understand the structure of DNA in a cell.In prokaryotes-DNA IS NOT ENCLOSED IN A NUCLEUS.Whereas in Eukaryotes-DNA is enclosed in a nucleus.\nSince you want to understand the structure of DNA.\nlets look at its components first\nmonomer of DNA IS NUCLEOTIDE\neach nucleotide is made up of Deoxyribose sugar,Phosphate group and any of the 4 nitrogenous base I.E. ADENINE(A)\nGuanine(G),Thymine(T) and Cytosine(C).Base pairings A-T AND G-C ALWAYS.\nPrimary structure of DNA IS  like a ladder structure and then it forms the DOUBLE HELIX STRUCTURE AND THEN IT GOES TO super coil stage known as Tertiary structure and last is Quartenary structure or chromosome stage, you don't always see DNA in its quartenary stage only when its undegoing cell division otherwise mostly you will see DNA in a supercoil state i.E. Tertiary stage.
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it holds the nucleus together. there is a another force acting that is stronger than the repulsion of the protons for each other known as strong nuclear force
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the nucleus??\ndna is stored??yes??
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do you mean interactions BETWEEN nucleic acids and proteins?  If so there's a lot of ways you can study that - you can do a footprint analysis - digest the nucleic acid in the presence of the protein and see what piece gets protected to see where the protein binds if you know the identity of the two interacting molecules.  If you don't know their identity you can try a gel-shift assay where DNA will move at different rates on a gel in the presence and absence of various proteins.  If you know the protein but not the DNA you can try an affinity column with the protein immobilized and then try to determine which DNA sequences bind.  You can also try to determine the crystal structure of a co-crystal if you have a lot of the two materials.  good luck!
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A strand of DNA, the double helix, is acutally two molecules, one on each side of where the 'rungs' connect. \n\n"DNA macromolecules as people typically think of them are not single molecules. Rather, they are pairs of molecules, which entwine like vines to form a double helix"-- 1\n\nDNA is about 2 nanometers wide.  Since electron microscopes have a resolution that can make out 78 picometers (.078 nanometers) we could see a single molecule of DNA. --2
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Space-filling model of a section of DNA moleculeDeoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions specifying the biological development of all cellular forms of life (and most viruses). DNA is a long polymer of nucleotides and encodes the sequence of the amino acid residues in proteins using the genetic code, a triplet code of nucleotides. \n\nIn complex cells (eukaryotes), such as those from plants, animals, fungi and protists, most of the DNA is located in the cell nucleus. By contrast, in simpler cells (prokaryotes) such as bacteria, DNA is not separated from the cytoplasm by a nuclear envelope. The energy-generating organelles known as chloroplasts and mitochondria also carry DNA. \n\nDNA is often referred to as the molecule of heredity as it is responsible for the genetic propagation of most inherited traits. These traits can range from hair colour to disease susceptibility. During cell division, DNA is replicated and can be transmitted to offspring during reproduction. Lineage studies can be done based on the facts that the DNA in mitochondria (mitochondrial DNA) only comes from the mother, and the male "Y" chromosome only comes from the father. \n\nEvery person's DNA is inherited from both parents. The mother's mitochondrial DNA together with twenty-three chromosomes from each parent combine to form the genome of a fertilized egg. As a result, with certain exceptions such as red blood cells, most human cells contain 23 pairs of chromosomes, together with mitochondrial DNA inherited from the mother. DNA Overview Unsolved problems in biology: Do all organisms link together to a primary source? Given a DNA sequence, what shape will the protein fold into? Given a particular desired shape, what DNA sequence will produce it? What are all the functions of the DNA? The building block of life may be a precursor to a generation of electronic devices and computers, but what are the electronic properties of DNA? Is junk DNA only molecular garbage?\nDNA Under electron microscopeThis section presents a simple (but admittedly unsophisticated) overview of DNA. \nGenes can be loosely viewed as the organism's "cookbook" or "blueprint"; \nA strand of DNA contains genes, areas that regulate genes, and areas that either have no function, or a function we do not (yet) know; \nDNA (for DeoxyriboNucleic Acid) differs from RNA by having the sugar 2-deoxyribose instead of ribose in its backbone. This is the basic chemical distinction between RNA and DNA. \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, with U rarely replacing T, notably in PBS1 phage DNA; each base "pairs up" with only one other base: A+T or U, T or U+A, C+G and G+C; that is, an "A" on one strand of double-stranded DNA will "mate" properly only with a "T" or "U" on the other, complementary strand; \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 order of the bases along the length of the DNA is the genetic material, the sequence itself is the description for genes; \nThe cell begins DNA replication by forcibly unzipping the DNA double strand down the middle, and then recreates the "other half" of each new single strand by drowning each half in a "soup" made of the four bases. An enzyme makes a new strand by finding the correct "base" in the soup and pairing it with the or
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The mode by which DNA replicates. Each strand acts as a template for a new double helix. The established model of DNA replication in which each double-stranded molecule is composed of one parental strand and one newly polymerized strand.
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Although sometimes called "the molecule of heredity", DNA macromolecules as people typically think of them are not single molecules. Rather, they are pairs of molecules, which entwine like vines to form a double helix (see the illustration at the right).\n\nEach vine-like molecule is a strand of DNA: a chemically linked chain of nucleotides, each of which consists of a sugar (deoxyribose), a phosphate and one of five kinds of nucleobases ("bases"). Because DNA strands are composed of these nucleotide subunits, they are polymers.\n\nThe diversity of the bases means that there are five kinds of nucleotides, which are commonly referred to by the identity of their bases. These are adenine (A), thymine (T), uracil (U), cytosine (C), and guanine (G). U is rarely found in DNA except as a result of chemical degradation of C, but in some viruses, notably PBS1 phage DNA, U completely replaces the usual T in its DNA. Similarly, RNA usually contains U in place of T, but in certain RNAs such as transfer RNA, T is always found in some positions. Thus, the only true difference between DNA and RNA is the sugar, 2-deoxyribose in DNA and ribose in RNA.\n\nIn a DNA double helix, two polynucleotide strands can associate through the hydrophobic effect and pi stacking. Specificity of which strands stay associated is determined by complementary pairing. Each base forms hydrogen bonds readily to only one other -- A to T and C to G -- so that the identity of the base on one strand dictates the strength of the association; the more complementary bases exist, the stronger and longer-lasting the association.\n\nThe cell's machinery is capable of melting or disassociating a DNA double helix, and using each DNA strand as a template for synthesizing a new strand which is nearly identical to the previous strand. Errors that occur in the synthesis are known as mutations. The process known as PCR (polymerase chain reaction) mimics this process in vitro in a nonliving system.\n\nBecause pairing causes the nucleotide bases to face the helical axis, the sugar and phosphate groups of the nucleotides run along the outside; the two chains they form are sometimes called the "backbones" of the helix. In fact, it is chemical bonds between the phosphates and the sugars that link one nucleotide to the next in the DNA strand.
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DNA is a double helix molecule.  The 2 strands are aniparellel (one runs 3' to 5' and the other 5' to 3').  The DNA says in the nucleus of the cell.  The way it replicates is that in uncoils itself and separated from the other strand.  Because of the 4 different nucleotides it is simple to replicate.  The nucleotides are shown as A,C,T, and G.  G goes with C, and T goes with A.  After the stands have separated the nucleotides that are floating about attach themselves to the proper match.  They attach themsleves using an enzyme called DNA polymerase. Now you have 2 complete DNA strands.
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Could be one of two things:\n\n1) a portion of the DNA is replicated so that it can be towed out of the nucleus and used to direct cellular activities.\n\n2) the entire strand of DNA is replicated at the beginning of cellular division, with one copy going to each new cell.