whats the reason for getting 3 bands instead of one band in seperation of dna plasmid bu gel electrophoresis?
962756
OK, so if you don't digest plasmid you'll get three bands:\n\nlinear, nicked and supercoiled.\n\nHowever, you did digest it, with 2 enzymes with 1 site each (I think?).\n\nA complete digestion would yield 2 bands.  Incomplete digestion would give those two bands, plus linearized (single cut, either enzyme).
944914
it's almost the same theory but the stuff (eg, buffers and gel types) used are different. Also proteins separate according to their molecular weight and DNA separate according to their base pairs.
722061
polyacrylamide Gel Electrophoresis
945093
The subscrips indicate that mulitples of the symbol they follow.  Like the AgNO3 the three means that there are 3 oxygens.  The two after the () means there are three whole molecule though, that can be placed infront as a coeffient.
826482
As I recall, the map unit is a 1% chance that two genes will sort independently. So, 13% will be al/+ phenotype, 13% dp/+, 37% are al/dp, and the other 37% are wildtype. I think... definitely check this before you accept it as true.
627185
the gel is like a matrix which offers reistance to the fragments of dna.  the dna has polarity which means it will be effected by electric current.  when the electricity passes through the gel and the wells with the sample, it picks up bits of the dna and carries it toward the other end of the gel.  smaller pieces hit less resistance from the gel and travel quicky.  larger pieces hit more resitance and travel slowly.  \n\nusually there will be a control or a ladder that will travel along at the same time.  you can compare the distance your dna fragments travel to the ladder and you'll know aproximately how many base pairs are in each band.
133925
have you tried an extraction buffer containing SDS then precipitate the DNA and give it a wash or 2 with 70% EtOH to help remove the SDS?  that's what we used with maize instead of CTAB.
11574
Both answers are correct, except for the "no" part. Agarose is made from seaweed and when heated in a buffer, cools to form a gel. The gel is used for gel electrophoresis, which is used to separate DNA fragments of different sizes.\n\nThe question is kind of funny though, because if you are doing genotyping, you should know a bit of this.
1098660
Your question isn't easy to read, but i think i understand it enough. There is one mole of 1kbp DNA strand with an EcoR1 restriction site in the middle. The amount of 5'ends produced when you addd EcoR1 to the DNA will be double because you will be effectively cutting the DNA in half. I hope this is what you were asking
837041
it's not 1 or 2 because they're nucleotide bases\n\n3 is the only chioce left
103798
When DNA fingerprinting first began, restriction fragment length polymorphism (RFLP) analysis was used, though it has been almost completely replaced with newer techniques. RFLP analysis is performed by using a restriction enzyme to cut the DNA into fragments which are separated into bands during agarose gel electrophoresis. Next, the bands of DNA are transferred via a technique called Southern blotting from the agarose gel to a nylon membrane. This is treated with a radioactively-labelled DNA probe which binds to certain specific DNA sequences on the membrane. The excess DNA probe is then washed off. An X-ray film placed next to the nylon membrane detects the radioactive pattern. This film is then developed to make a visible pattern of bands called DNA fingerprinting. By using multiple probes targeting various polymorphisms in successive X-ray images, a fairly high degree of discrimination was possible. The primary drawback of RFLP is that the exact sizes of the bands are unknown and comparison to a molecular weight ladder is done in a purely qualitative manner. Many labs developed policies that described what they considered a unique band, but it was not standardized and led to DNA fingerprinting coming under harsh attack in People v. Castro 545 N.Y.S. 2d. 985 (Sup. Ct. 1989). RFLP was a very time consuming method which required relatively high quantity of good quality DNA to be used (such as a dime sized blood drop). This made typing degraded samples such as those from evidence that had been exposed to the elements fairly difficult.
565191
I think that the easiest way to do this is by enumeration. \n\nIf there are 3 red beads in a row the 3 blue beads have to be in a row. That's pattern 1.\n\nIf no red bead touches any other red bead, then the pattern has to be RBRBRB. That's patern 2.\n\nIf the red beads are split 2 and 1.\nThen the pattern has to be RRBBRB or RRBRBB.\nIf you flip the first pattern over (which you could do with a bracelet) they are the same, so that's only one pattern.\n\nSo 3 patterns total.
965097
The stages of DNA isolation include\n    1) homogenization of thymus in a buffered isotonic sucrose-detergent solution\n    2) increasing the osmolarity with saline\n    3) centrifugation to remove cellular debris\n    4) decantation of the supernatant into a clean beaker\n    5) precipitation of the DNA by layering cold ethanol on the top of the supernatant\n    6) spooling of the precipitated DNA\n\nCheck out the website... im sure thats pretty much all you'll need :)\n\nhttp://www.biology.clc.uc.edu/fankhauser/Labs/Genetics/DNA_Isolation/Thymus_DNA.htm
116584
The PCR process consists of a series of twenty to thirty cycles. Each cycle consists of three steps \n\n The double-stranded DNA has to be heated to 94-96°C in order to separate the strands. This step is called denaturing; it breaks apart the hydrogen bonds that connect the two DNA strands. Prior to the first cycle, the DNA is often denatured for an extended time to ensure that both the template DNA and the primers have completely separated and are now single-strand only. Time: 1-2 minutes.\n\n\nAfter separating the DNA strands, the temperature is lowered so the primers can attach themselves to the single DNA strands. This step is called annealing. The temperature of this stage depends on the primers and is usually 5°C below their melting temperature (45-60°C). A wrong temperature during the annealing step can result in primers not binding to the template DNA at all, or binding at random. Time: 1-2 minutes.\n\nFinally, the DNA-Polymerase has to fill in the missing strands. It starts at the annealed primer and works its way along the DNA strand. This step is called extension. The extension temperature depends on the DNA-Polymerase. The time for this step depends both on the DNA-Polymerase itself and on the length of the DNA fragment to be amplified. As a rule-of-thumb, 1 minute per 1000bp.\n\n\nRestriction Fragment Length Polymorphism (RFLP) is a technique in which organisms may be differentiated by analysis of patterns derived from cleavage of their DNA. If two organisms differ in the distance between sites of cleavage of a particular restriction endonuclease, the length of the fragments produced will differ when the DNA is digested with a restriction enzyme. The similarity of the patterns generated can be used to differentiate species (and even strains) from one another.
985064
Loops and other structures are caused when there is repetitive sequences within the DNA sequence so there is more than one place where a re-annelaing strand can make a match. Then, instead of pairing with the correct part of the sequence the DNA makes a pair somewhere else and the part that it should have paired with loops out.\n[It would be easier to explain if I could draw it!]
851316
I think I might be qualified to answer this question.\n\nDNA is separated in an electrophoretic field based on the size of the molecules.  \n\nImagine wet spaghetti strands (all different sizes) passing through a thick block of Swiss cheese.   Agarose electrophoresis is based on the ability of the smaller molecules to pass through holes easier than the larger molecules.\nThe smaller the mass, the more nimble it is, and the quicker it can manage all those "Swiss cheese" holes that agarose gels naturally have.\n\nOnce the DNA has run through the gel for a sufficient amount of time, you can stain the gel (actually you can stain the gel as the DNA moves through the gel too).  \n\nThe stain (the classic one is ethidium bromide, but there are others) has a propensity to squeeze itself between nucleotides on both strands.  When it is exposed to a transilluminator light  with a specific wavelength, the ethidium bromide will fluoresce and can be photographed for a permanent record.  \n\nAnalysis is typically based on running controls (positive and negative controls) and a size ladder along with the "unknown" PCR amplicon.  Usually I can predict the size of my unknown amplicon before I run the reaction. \n\nI can then choose a size ladder that will at least give me a rough idea of the size of my amplicon I expect. The ladder also allows me to observe any other false amplicons created during the PCR.  Additionally, some like to estimate how much PCR amplicon was generated in the reaction by comparing the intensity of the size ladder with the intensity of the amplicon. \n\nI hope I was able to help in answering your question.  Hoping YOU spread the good Karma!
84160
rflp's are restriction fragment length polymorprhisms. Restriction fragments are obtained by taking a length of DNA and cutting it with restriction enzymes. Restriction enzymes are enzymes which cut DNA at a specific sequence and only that sequence. So the enzyme searches thru the DNA chain for a sequence that it can work on (there are different enzymes which work with different sequences) and cuts. If you take a chromosome and incubate it with your preferred enzyme the chromosome will be cut at specific sites wherever they appear in the sequence. This will give you a given number of fragments. Now each person's chromosomes are slightly different so if you took say your chromosome 1 and my chromosome 1 and incubated them both with a set restriction enzyme the majority of cuts would be done in the same place. But if I, for example, had a mutation in one of the sites preventing the enzyme from recognizing it i would have one long fragment where you have two. this is a polymorphism (a difference). Forensics Teams use this technique to look at DNA to find differences between individuals (you will have polymorphisms in common with both your parents but not quite the same but a higher resemblance to them than you would to me)\n\nhope thats semi clear - and good basic genetics book should help further e.g. Essential Genetics by Hartl and Jones