how DNA generates diversity?
152438
#1)  Primarily by mutation.  A mutation must occur a germ cell (cells that produce sperm and eggs).  This can produce progeny with novel traits.  This is fairly rare event (one out of every billion nucleotides copied during meiosis).  Our body has ways of fixing these errors, but this is the biological basis of evolution.\n#2)  By crossing over.  During meiosis, parental chromosomes will swap pieces with each other.  For example, I used pieces of my mother's chromosome #1 and my father's chromosome #1 when I made the chromosome #1 that I passed to my daughter.  I passed a different combination of pieces to construct a chromosome #1 for my second daughter.\n#3)  By independent assortment during meiosis.  So not only did I make novel chromosomes out of pieces of my parents chromosomes, but I created a gamete using a unique combination of my mother and father's chromosomes.  For example I might have used chromosomes 1-11 of my father's (with pieces of my mother's chromosomes 1-11) and numbers 12-22 of my mother's (with pieces of my father's chromosomes 12-22).  For my second daughter it could have been totally different.  It is a unique situation each time!  No two gametes are the same.
547089
Genetic variability allows a group to adapt to changes in habitat, climate, etc- so, for example, if it became suddenly dry for many years, frogs that carried genes that helped them adapt to that would survive, and thus save that population of frogs.  If you look, for example, at humans- some humans are extremely efficient at storing fat- in days gone by, there were probably periods when there was no food for months.  Most people would have died, but these people (who nowadays are obese and have a hard time) would have survived and saved that population of humans.  Diversity is the single best strategy for dealing with environmental stresses that would otherwise wipe out a population.\n*edit* in response to your email- There are a lot of genes that are there for sepcific stress conditions- times when things are not normal, like a period when there isn't any food, or water, or a long period of cold, or apecific diseases.  The more of these kinds of genes a population has in it, the better the chance that at least  few of the population will survive.  For example, say there are 100 diseases that can kill frogs.  There are a thousand frogs in the population- say each frog only has a few of the 100 genes that protect from the diseases.  So, if you have a major disease come through, maybe half the population will die (the ones that didnt have the gene to protect against that disease).  Now, right away, there is a period of drought, and another half die (cause they didnt have the gene to help them survive drought)...and on and on- you can see how, having a lot of different genes (high diversity) would help the whole population survive getting hit with different environmental stresses like disease, parasites, hot and cold weather, etc.  If a population of frogs had only the genes they needed to live in their little pond, in exactly the right weather, with exactly the right amount of food (in other words, they had low genetic diversity) then if any disease, or drought or cold snap came through, it would wipe them out.
401402
The base pair sequence is identical in every cell of a given human (barring oddities like chimeras).\n\nWhat differs is the genes that are active and inactive.  Sometimes base pair methylation is used for that; sometimes, binding of the DNA to histones or other protein (and probably RNA) molecules turn off or turn on genes, etc.  It's sort of like a piano--all the keys are there for every performance.  It's just that some are struck, and others not.  (And you'd probably rather listen to someone other than me playin' it...)  Depending on the order of the striking of the keys, and the combinations of keys struck at different times, you get different pieces of music.\n\nSimilarly the sequence and pattern of genes turned on and off generates different kinds of cells, even though the DNA is essentially identical.
341693
The mother and child will have *nearly* identical DNA.  There will be a few mutations because mutations are ubiquitous, but 99.99+% of their DNA will be the same.
412034
There are various methods to sequence.\nThe current method is have a primer that can anneal to a segment prior to the region you wish to sequence. You then extend the primer using a polymerase, dNTPs and fluorescent terminating nucleotides.  Once the fluorescent terminating nucleotide is incorporated the sequencing is terminated for that sequence.  You will end up with a collection of DNA fragments of different lengths that are a copy of the DNA you wish to sequnce.  These fragments are run through a gel and separated based on size.  Each terminating fluorescent nucleotide is a different color for A, C, G and T.  Based on which fluorsecent nucleotide is present at position you know the nucleotide that is there due to the color. \nFrom this you get the DNA sequence.\nWasn't that easy!
513565
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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Dispersive replication of DNA was a model of replication which has been proven wrong. If replication were dispersive, both strands of the parental DNA would be cut into small bits and new DNA would be synthesized to fill the gaps. This way, new DNA strands would contain an equal amount of old and newly sythesized DNA. After, say, 3 rounds of replication, the old DNA would be equally dispersed among the eight DNA molecules.\nJust remember that the actual form of replication in cells is the semi-conservative one.
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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
145878
In nature, living things evolve through changes in their DNA. In an animal like a chicken, DNA from a male sperm cell and a female ovum meet and combine to form a zygote -- the first cell of a new baby chicken. This first cell divides innumerable times to form all of the cells of the complete animal. In any animal, every cell contains exactly the same DNA, and that DNA comes from the zygote. \n\nChickens evolved from non-chickens through small changes caused by the mixing of male and female DNA or by mutations to the DNA that produced the zygote. These changes and mutations only have an effect at the point where a new zygote is created. That is, two non-chickens mated and the DNA in their new zygote contained the mutation(s) that produced the first true chicken. That one zygote cell divided to produce the first true chicken. \n\nPrior to that first true chicken zygote, there were only non-chickens. The zygote cell is the only place where DNA mutations could produce a new animal, and the zygote cell is housed in the chicken's egg. So, the egg must have come first.
1076502
Once you put a current across the gel, the DNA is carried through the gel due to its negative charge.  If a mixture of different sized pieces of DNA are loaded, they will be separated based on their size; smaller pieces will travel faster than larger ones.
514661
DNA is used to create many different kinds of protiens.  It is the template that your body uses to create them.
417879
This question appears regularly in the question file, so let's take a shot at it. \n\nIn nature, living things evolve through changes in their DNA. In an animal like a chicken, DNA from a male sperm cell and a female ovum meet and combine to form a zygote -- the first cell of a new baby chicken. This first cell divides innumerable times to form all of the cells of the complete animal. In any animal, every cell contains exactly the same DNA, and that DNA comes from the zygote. \n\nChickens evolved from non-chickens through small changes caused by the mixing of male and female DNA or by mutations to the DNA that produced the zygote. These changes and mutations only have an effect at the point where a new zygote is created. That is, two non-chickens mated and the DNA in their new zygote contained the mutation(s) that produced the first true chicken. That one zygote cell divided to produce the first true chicken. \n\nPrior to that first true chicken zygote, there were only non-chickens. The zygote cell is the only place where DNA mutations could produce a new animal, and the zygote cell is housed in the chicken's egg. So, the egg must have come first.
937500
Many times what happens is a specific gene or stretch of DNA is duplicated in an organism.  If this doesn't cause any harm, one copy of the gene can mutate, leaving the other one intact to carry out its original function.  The extra gene can then become something entirely different over time, occasionally mutating into something useful.  \nA word of warning- don't start with a belief and look for the evidence.  You will find evidence (not good or true evidence, but you will find something) for whatever you go out looking for, especially on the internet.  Find the evidence first and see where it leads you, or you will end up very, very wrong about some important things.
395275
In nature, living things evolve through changes in their DNA. In an animal like a chicken, DNA from a male sperm cell and a female ovum meet and combine to form a zygote -- the first cell of a new baby chicken. This first cell divides innumerable times to form all of the cells of the complete animal. In any animal, every cell contains exactly the same DNA, and that DNA comes from the zygote.\n\nChickens evolved from non-chickens through small changes caused by the mixing of male and female DNA or by mutations to the DNA that produced the zygote. These changes and mutations only have an effect at the point where a new zygote is created. That is, two non-chickens mated and the DNA in their new zygote contained the mutation(s) that produced the first true chicken. That one zygote cell divided to produce the first true chicken.\n\nPrior to that first true chicken zygote, there were only non-chickens. The zygote cell is the only place where DNA mutations could produce a new animal, and the zygote cell is housed in the chicken's egg. So, the egg must have come first.
374098
Obviously you dont know how things work.\n\nCheck this out, a fish cannot give birth to a different species fish. What if a mutation occurs and the fish has a extra fin? Due to natural selection that fish is better suited to the environment, and mates more and the mutation becomes more often, vwooleh, we have a new species of fish assuming the other just pure breeds or it has migrated away.\n\nWe all started very basic, that basic thing mutates and mutates into say 10 basic things, those basic things become more complex and so those 10 basic things multiply into 100 more complex things each only breeding within its own mutation.
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They are different varieties due to different in DNA color sequence.This is regulated by gene regulation and expression by making novel proteins.
846207
atgc strands adenine, guanine, thymine, cytosine, combinations are unique for individuals and are a part of the genepool brought teogether by set og genes from both parents, thus carrying in them a part of each, karyatyping is done to trace ancestry.