What is the function of agarose gel in electrophoresis?
83716
agarose forms a matrix the DNA or RNA fragments have to pass through when the current is applied.  the longer the nucleic acid fragments the harder it is to pass though the gel so the fragments seperate by size.
995950
Radial immunodiffusion quantitatively determines the level of an antigen. Antibody is incorporated into liquefied agar and allowed to gel. The antigen is introduced by small circular wells. Radial immunodiffusion is both sensitive and quantitative. It is used clinically to detect patient levels of blood proteins. None of the experiment components contain human serum.
343960
Detection of specific DNA fragments by gel-transfer hybridization (Southern blotting). (A) The mixture of double-stranded DNA fragments generated by restriction nuclease treatment of DNA is separated according to length by electrophoresis. (B) A sheet of either nitrocellulose paper or nylon paper is laid over the gel, and the separated DNA fragments are transferred to the sheet by blotting. The gel is supported on a layer of sponge in a bath of alkali solution, and the buffer is sucked through the gel and the nitrocellulose paper by paper towels stacked on top of the nitrocellulose. As the buffer is sucked through, it denatures the DNA and transfers the single-stranded fragments from the gel to the surface of the nitrocellulose sheet, where they adhere firmly. This transfer is necessary to keep the DNA firmly in place while the hybridization procedure (D) is carrried out. (C) The nitrocellulose sheet is carefully peeled off the gel. (D) The sheet containing the bound single-stranded DNA fragments is placed in a sealed plastic bag together with buffer containing a radioactively labeled DNA probe specific for the required DNA sequence. The sheet is exposed for a prolonged period to the probe under conditions favoring hybridization. (E) The sheet is removed from the bag and washed thoroughly, so that only probe molecules that have hybridized to the DNA on the paper remain attached. After autoradiography, the DNA that has hybridized to the labeled probe will show up as bands on the autoradiograph. An adaptation of this technique to detect specific sequences in RNA is called Northern blotting. In this case mRNA molecules are electrophoresed through the gel and the probe is usually a single-stranded DNA molecule.
497626
here're some informative links http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/E/Enzymes.html , http://en.wikipedia.org/wiki/Enzyme\n\nhope this helps.
141967
The well in the chamber is to contain the buffer solution. The well in the agarose is to contain the sample.\n is that what you needed??
1177839
it used to be isolate the pathogen from an infected host and use it to infect a healthy animal, but i believe they are now using the third choice more because the second choice doesn't always work.  so i would say isolate bacterial/viral proteins by electrophoresis.
310596
The first question is what are you trying to accomplish. The amount of material will direct you to one method.  Also, the polarity of your material will dictate the method you will employ.  Silica gel columns are relatively cheap and will work for most things but not all. They also tend to be more useful for larger scale chromatography in terms of speed and convenience. Reverse phase columns are expensive and require expensive equipment and detectors.  However, they will separate material more efficiently than a silica gel column but the scale will be smaller.  If your material is chiral then you need chiral columns which are very expensive and also need special equipment like reverse phase equipment.  Lastly, there are additional method like gas chromatography, ion exchange, capillary electrophoresis and other less commonly used methods which all have some utility based on the first statement.
345158
The function of DnaB helicase is to couple ATP hydrolysis with the unwinding of the DNA double helix at the replication fork, creating two antiparallel strands of ssDNA. DNA polymerase and DnaB helicase are complexed via the tao subunit of DNA polymerase which serves to stabilize the hexameric structure of the helicase. This now immobilized protein complex allows for DNA to pass through it. There are other helicases involved with replication but this is the only one found to be essential (knockout mutations are fatal) and the only one that can stimulate primase. If you need more info, please formulate a somewhat more coherent and specific question.
458712
Beta-galactosidase :o)
838778
To be honest with you i don't quite understand your question, it is often that restriction enzymes are used to create genomic library for which you look into the overlapping sequence and then be able to determine which fragment is next to which. If that is what you have done, you should have used the fragmented DNA sequence to determine the orginall DNA sequence that you digested it with the enzyme, to confirm the sequence you ahve found is correct, you can use PCR, you got the hypothetical sequence, thus by making primers from the start and the end of the sequence (doesn't matter which way round) you should have amplify the same sequence which you started with, you got the amplified DNA (same as the orginal DNA because you used primers that complemented the very start and the very end of the sequence which you found out after the restruction enzyme mapping) run it on gel electrophoresis with a DNA size marker that will include the size of DNA you have sequenced, if the amplified DNA size is the same as the sequence you have found from restriction mapping, that means your primers did complemented from the start and the end, that means the sequence you thought is actually the correct sequnece.\nI am sorry, i don't think i am making this clear enough, but anyway, that's the best i can think of.
653429
Yes proteins are amphoteric, they do contain both acidic and basic residues, but the charge on the protein is dependent on the degree of dissociation of the acidic or basic groups. \n\nThe Tris-HCl buffer used in gel electrophoresis(assuming you are talking about PAGE, most commonly used for proteins) has a pH of 8.7. At this pH the protein molecules have a net negative charge, hence they move towards the positive electrode. Their difference in mass leads to their separation as does the amount o charge that they carry.\n\nIsoelectric focusing uses the amphoteric nature of proteins to the max - it uses the isoelectric point of the protein for its separation. The isoelectric point is the pH at which the protein has no charge and hence it stops moving in the electric field.
358716
What you are referring to is probably one of the low, flat plastic trays used in the process of developing film and prints.  They are inexpensive, and can be handy for performing experiments where you need a large surface, but low volume of water -- such as the experiment where you calculate Avogadro's Number by determining the area covered by a droplet of a dilute solution of oleic acid.\n\nThey can also be useful for containing/controlling small parts that might roll away on a hard lab bench surface.\n\nJust a few ideas.
580906
Its a buffer and a metal chelating agent. \nIt prevents metallo proteases and nucleases from funcitoning fully as well as stabilizing the pH of the buffer. \n\nRegards
177423
It binds to a specific sequence of the gene. If the gene is present, it will bind, if not, it will not bind. Usually the probe also has a fluorescence end, therefore you can use a light to show that it did bind or not.
99069
what for? for a DNA gel to separate 1000 bp to 10000 bp I'd try a 0.7 % gel (i.e. 1.4g in 200 ml). and run it for 30-45 min (watch the bromophenol blue) this is about 500bp
763923
In SDS-PAGE you have the formation of a complex between SDS and proteins so that you have anegatively charged SDS molecule for approximately every two amino acids in the protein. This means that the protein-SDS complex will have a huge negative charge that will mask any charge of the protein itself and force the protein-SDS complex to move towards the positive electrode.\n\nI've never heard of the other thing you are mentioning. Could you expand on that? Hydrophobicity of what? DNA has a large negative charge due to its phosphate backbone and that's the reason it migrates during electrophoresis.
1175970
well..\nlike they mentioned earlier ,plasmolysis is an important process for plants..but it also has a lot of commercial purposes.\nnot only is it used in jams and pickles to prevent bacteriafrom surviving in them it is also used for some blood tests.