Do identical twins have the same DNA strand structure?
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Twins are of two types 1) Fraternal 2) Zygotic.\n \n1) The fraternal twins develop from two different eggs that are fertilized at one and the same time.\n In this case DNA strands may not be identical. Mostly they are not.\n\n2) Zygotic, Identical or Siamese twins develop from only one fertilized egg. It splits early in to two and both the halves develop in to full-fledged individuals. Only in such cases the DNA is IDENTICAL.The sex is also the same.\n  Where as in fraternal twins the sex also be different , one boy and the other girl. It is like two siblings born together.
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DOUBLE-STRANDED HELIX
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No, a clone would be exactly like an identical twin (though with a clone the two may be different ages).  Though there are a lot of reports of twins feeling when the other is hurt or dies, most twins interviewed claim this has never happened to them.  Regardless, even in those that claim to be able to "feel" the other's pain, there is no damage or lasting effect.  There of course may be psychological damage if, for example, you were raising your clone as a child or were close to them (as identical twins often are)-depression, grief, etc, but that is quite normal.
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As an identical twin, I will answer this question.\n\nNo, twins do not have identical fingerprints.\n\nIdentical twins have identical DNA. However, it more than DNA that shapes a fingerprint.  Events during the growth of fingerprints ( and other development processes) will change the course of the prints - ie. a twin's finger brushes against the uterine wall, causing an 'abrasion' which alters the course of the print... one twin recieves less blood / nutrients than the other, affecting the rate of growth etc..\n\nFingerprints are a mixture of DNA and life events, as is the development of any individual. My fingerprints are 'similar' to my twins, but not identical - we have compared. We have the same basic loops and swirls, but some are opposite, different lengths, etc.. \n\nHope this helps.
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4.  DNA is double stranded so if it replicates once you have four strands.
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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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Each chromosome in your body has an "identical pair"- there are two chromosomes that code for the same functions- one from your mother and one from your father.\n\nBecause they come from two sources, they are coding for the same functions, but may code differently for them (ie blue eyes as opposed to brown eyes).\n\nDuring prophase one, each chromosome duplicates into two sister chromatids joined by a centromere, and then the double stranded chromosome finds it's partner which is coding for the same thing (just came from the opposite parent), and is also double stranded.  Now you have a 4 stranded tetrad.\n\nGenetic variability comes from crossing over.  This is where the two chromatids closest together in the tetrad exchange some genetic information.\n\nFor example, two of the chromatids code for blue eyes, brown hair and shortsightedness.\nThe other two chromatids code for brown eyes, red hair and normal vision.\n\nDuring crossing over one chromatid from each pair forming the tetrad literally have ends "crossing over" and bits of information are exchanged.\n\nAfter crossing over, you have 4 chromatids with unique codings.  Using the example above, we may now have:\n-blue eyes, brown hair, shortsightedness\n-blue eyes, red hair, normal vision\n-brown eyes, brown hair, shortsightedness\n-brown eyes, red hair, normal vision\n\nWe now have genetic variability in each gamete produced from this meiotic division.
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DNA is in chromosomes. Chromosomes are in 23 pairs: 2 *different* copies of Chromosome 1, 2 different copies of C2, etc, in each person.  Whether you get your father's Chromosome 1 that he got from his mother, or the one he got from his father, is random with respect to which Chromosome 2 you get from your father. Same goes for your siblings. The chances of two nontwin siblings getting the same exact set of 23 5chromosomes from one parent are vanishingly small. The chances of siblings getting the same exact set of 23 chromosomes from EACH parent are .. well, it's essentially impossible. \n\nSame goes for the possibility that they would receive NO chromosomes in common - although it is theoretically possible to have siblings that share no genetic relation at all.\n\nDNA evidence is never 100% conclusive, but the tests that are widely used (if done properly) have such a small possibility of being wrong that they might as well be 100% conclusive. That's because there's just so much genetic material in any one person, it averages out ... makes it so that siblings are actually very close to 50% alike - even though they could be anywhere from 0 to 0% alike, in theory.
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DNA is a double helix, has deoxyribose sugar, and the nitrogen base thymine.\n\nRNA is a single strand, has ribose sugar, and the nitrogen base uracil (instead of thymine).
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No; there are random / environmental factors at work, as well as heritable factors.\n\nThe % of loops and whorls in prints of fingers / toes is similiar in identical twins, but not identical in placement, nor in other fine detail.\n\nHey! look at your own left and right sides!  The exact placement of veins visible through skin eg at wrist and elbow, or exact fingerprints, is not the same when you compare your 2 sides!  They have identical DNA .... but those random factors affected them differently.
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Chromosome Terms before and after DNA Duplication (Replication)\nNote: Duplication and replication mean exactly the same thing.\n• An unduplicated chromosome is one chromosome. A chromosome more or\nless consists of two arms that extend from a narrow "centralized" region called\nthe centromere. The centromere region is often visible when chromosomes\nduplicate.\n• When a chromosome duplicates, it becomes one duplicated chromosome,\nand the two copies remain attached to each other. Note it is still one\nchromosome.\n• The two exact copies of the duplicated chromosome, which remain attached by\nthe protein cohesin, are called "sister" chromatids. They are identical to\neach other. It is essential that you remember this!\n• At the centromere region of the duplicated chromosome, structures (made of\nprotein and DNA) called kinetochores form during division. The three-layered\nkinetochores attach to microtubules of the spindle during mitosis. The\nkinetochores of the two sister chromatids face in opposite directions.\nKinetochore – TEM\n• After the identical sister chromatids are separated during mitosis, each (called\na "daughter" chromosome now) becomes a single unduplicated chromosome\nagain.\nRemember: A chromatid must be attached to its identical chromatid and the two sister\nchromatids comprise one duplicated chromosome. "Sister" chromatids are not two\nchromosomes. They are one duplicated chromosome that consists of two identical\nchromatids. Once sister chromatids are separated they are no longer chromatids!
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Well, technically identical twins are clones and many organisms with asexual reproduction clone themselves, so yes. I think the question should be if an artificial clone can reproduce; but most of them don't even live more than a few days.
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I'm not sure how you intend to destroy one strand and not the other while the are rapped around each other, but the two strands can be easily separated using naturally occuring rep enzymes.\n\nIf the appropriate enzymes and nucleotides are present, the missing strand will be replaced with a new, identical strand.  In the absence of the appropriate components, the single-stranded DNA will continue to exist for a while, but will slowly degrade as it is less stable than the double-stranded form.  Also, the DNA will likely fold up on itself as there are almost certainly numerous regions which are complimentary to each other.\n\n__________\nDo you mean identical strands or complementary strands?  If they're identical, they're not two halves of a double-stranded molecule, so what happens to one will have no relation to what happens to the other.  If you mean complementary, you could stand to be a bit clearer on what you expect the laser to do to the strand that is irradiated.
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I think that you may be referring to lagging strand as opposed to leading strand?\n\nWhen DNA is replicated, the two strands separate, much like a zipper, along part of their length.  Unlike a zipper, the strands are oriented in opposite directions, called anti-parallel.\n\nThe new strand to be synthesized can only be synthesized in one direction.  This means that one strand can be built continuously.  The other strand will be built in small discontinuous segments which must then be connected.  This strand is known as the lagging strand.
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yes. only identical twins live in the same sack.
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No, identical twins are nearly identical in DNA-the only differences are in parts of the randomly sorted genes, and those would be different in the child as well, so couldn't be used for testing.
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the only DNA in a banana would be in the seeds, which are "banana embryos".  This DNA structure is the same as ours (double helix)