What is DNA? What are histones?
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DNA- deoxyribonucleic acid\nwhere the genes is made of. \nthe histones is the protein that pack DNA together to form chromosome!
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(Click to enlarge) \nDNA \ndouble-helix DNA model\nA. adenine\nT. thymine\nC. cytosine\nG. guanine\nD. deoxyribose\nP. phosphate\n(Academy Artworks) \nDNA (dē'ĕn-ā') \nn.\nA nucleic acid that carries the genetic information in the cell and is capable of self-replication and synthesis of RNA. DNA consists of two long chains of nucleotides twisted into a double helix and joined by hydrogen bonds between the complementary bases adenine and thymine or cytosine and guanine. The sequence of nucleotides determines individual hereditary characteristics.
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you can read up on it here\n\nhttp://en.wikipedia.org/wiki/DNA\n\nbut even better would be to buy related books and take related courses
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The DNA has to be wrapped up very tightly to fit all of it into the nucleus.  This is a complex process involving chromatin (DNA and associated proteins).  For example, histones are groups of protein molecules that the DNA strand wraps around to help compact its shape.  For a gene to be expressed (transcribed) a section of the the DNA has to become 'unwrapped' and 'exposed' to the transcription machinery.  Methylation and Acetylation of histones play significant roles in this process.\n\nAny good, recent, biochemistry textbook will explain these issues.  If you go to pubmed, they have an online book section.  Click on any of the biochemistry books and enter into the search field "DNA, chromatin", or "DNA, histones", or "gene expression, chromatin" and you will find lots of info. and probably pictures too.\n\nBest wishes and good luck.
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For DNA and RNA:\nhttp://www.visionlearning.com/library/module_viewer.php?mid=63\n\nOn fats:\nhttp://instruct1.cit.cornell.edu/Courses/ns421/Fats.html\n\nBy the way, DNA is a nucleic acid, but so is RNA\nDNA has deoxyribose sugar, while RNA has ribose\nDNA has adenine, thymine, guanine, and cytosine bases, while RNA has adenine, URACIL, guanine and cytosine.\nDNA is the "blueprint" and stays in the nucleus\nRNA has 3 types, messenger, transfer, and ribosomal\n\nHope this helps!!!
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Each cell contains our DNA makeup, it is protected inside the cell from bacteria, viruses and other harmful agents.  Without DNA our body would not be able to replicate and replace the cells which make up for example our organs or skin.  We are constantly producing new skin cells to replace the ones that we shed off every second.
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Deoxyribonucleic acid (DNA) is a nucleic acid —usually in the form of a double helix— 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 (a polynucleotide) and encodes the sequence of the amino acid residues in proteins using the genetic code, a triplet code of nucleotides.\nIn complex eukaryotic cells such as those from plants, animals, fungi and protists, most of the DNA is located in the cell nucleus. By contrast, in simpler cells called prokaryotes, including the eubacteria and archaea, DNA is not separated from the cytoplasm by a nuclear envelope. The cellular organelles known as chloroplasts and mitochondria also carry DNA.\nDNA is often referred to as the molecule of heredity as it is responsible for the genetic propagation of most inherited traits. In humans, 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 mitochondrial DNA only comes from the mother, and the male Y chromosome only comes from the father.\nEvery person's DNA, their genome, 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 zygote, the 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.\n\nMolecular structure:\nAlthough 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).\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.\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.\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 forming two hydrogen bonds and C to G forming three hydrogen bonds. The GC content and length of each DNA molcule dictates the strength of the association; the more complementary bases exist, the stronger and longer-lasting the association characterised by the temperate required to break the hydrogen bonding, its Tm value.\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.\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
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Proteins are the workhorses of an organism, providing everything from immunoresponse, enzymatic reactions, hormones and hormone receptors, and transport and channel proteins that move things in and out of cells. On top of all this proteins are the ultimate expression of our genes, since DNA codes for amino acids which form polypeptides which form proteins. Everything that makes you... you and all the features of other animals is the result of your genes expression in the form of proteins, like the color of your hairs and eyes. Proteins can also be a source of energy .\n\nI was going to complement Always Right's answer until I saw the wikipedia entry which it is copied and pasted from, it's fine to use sources (I'm using my bio 101 notes) but at least reference them, not say "Life"\n\nIt's also important to note that DNA is NOT a protein, DNA is a nucleic acid, a biological molecule separate from proteins.
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Yes, DNA is a polymer composed of four different nucleotides. The nucleotides are composed of phosphate and the sugar 2' deoxyribose, which make up the backbone of a molecule of DNA, and one of four nitrogenous bases: adenine (A), guanine (G), thymine (T), and cytosine (C). Bases on opposite DNA strands can form hydrogen bonds (A with T, and G with C), which hold the double-stranded molecule together. Polymerization of DNA occurs through the enzyme DNA polymerase, which catalyzes the synthesis of one of the DNA strands using the other strand as a template.
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DNA is double stranded with Deoxyribose, and has the nucleic acids Guanine, Cytosine, Thyamine, and Adenine (GCTA)\n\nRNA is single stranded with ribose, and has the nucleic acids Guanine, Uracil, Adenine, and Cytosine (GCUA)\n\nUracil replaces Thyamine
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A nucleosome is the fundamental repeating subunit of eukaryotic DNA, and is made up of DNA and histone proteins. It is found in the cell nucleus in eukaryotes. All chromatin (except for that packaged in the sperm nucleus) consists of nucleosomes. Nucleosomes can be seen with an electron microscope as bead-like structures along the DNA.\n\nThe histones make up the central core particle of the nucleosome. The DNA is wrapped around this protein complex in 1.6 turns, comprising about 145 base pairs. Together with the DNA linking two nucleosomes, there are about 200 bps of DNA per nucleosome.\n\nNucleosomes are involved in processes ranging from compaction of DNA to transcriptional control, and appear to be major carriers of epigenetically inherited information as well. Repeating nucleosomes with intervening "linker" DNA form the 10-nm-fiber, known descriptively as "beads on a string", and have a packing ratio of ~6, compared to "free" DNA (per nm length). A chain of nucleosomes can be arranged in a 30-nm-fiber, a compacted structure (thought to be a helical solenoid, a zigzag ribbon structure, a superbead, or having no regular structure) with a packing ratio of ~40. The H1 histone stabilizes this structure. Beyond 30 nm fiber the structure of chromatin is poorly understood, but it is classically suggested that the 30 nm fiber is arranged into loops along a central protein scaffold to form transcriptionally active euchromatin. Further compaction leads to transcriptionally inactive heterochromatin.
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dna is a chemical code inside every living cell that determines how the cell functions.
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DNA is the building blocks of life (I know you've heard that one). Basically, DNA encodes everything. It's what creates cells.\n\nIn a nutshell, DNA is comprised of a basic 5-carbon sugar with an attached nucleic acid (one of four, adanine, guinine, cytosine, and thiamine). These form long chaings that if stretched out fully would encompass the earth around 5 times. They encode (in a lengthy process) for protiens and certain protein chains that in the end, make your cells. And more cells, and more, until you get an organ. Enough organs and you get an organism. \n\n-Eric
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There is Histone and non-histone protein associated with the DNA.histone are low molecular protein made up of basic amino acids.Non histone are high molecular proteins and made up of basic amino acids.
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Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions for the biological development of a cellular form of life or a virus. All known cellular life and some viruses have DNAs. DNA is a long polymer of nucleotides (a polynucleotide) that encodes the sequence of amino acid residues in proteins, using the genetic code.\nDNA is responsible for the genetic propagation of most inherited traits. In humans, these traits range from hair color to disease susceptibility. The genetic information encoded by an organism's DNA is called its genome. During cell division, DNA is replicated, and during reproduction is transmitted to offspring.\n\nIn eukaryotic cells, such as those of plants, animals, fungi and protists, most of the DNA is located in the cell nucleus, and each DNA molecule is usually packed into a chromosome that are passed to daughter cells during cell division. By contrast, in simpler cells called prokaryotes, including the eubacteria and archaea, DNA is found directly in the cytoplasm (not separated by a nuclear envelope) and is circular. The cellular organelles known as chloroplasts and mitochondria also carry DNA. DNA is thought to have originated approximately 3.5 to 4.6 billion years ago.[1]\n\nIn humans, the mother's mitochondrial DNA together with 23 chromosomes from each parent combine to form the genome of a zygote, the 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. Lineage studies can be done because mitochondrial DNA only comes from the mother, and the Y chromosome only comes from the father
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DNA has the original code (for proteins) and RNA is the copy(of DNA) that leaves from the nucleus. Because DNA can't leave the nucleus so RNA copies the "code" from DNA.
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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