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The pore size of an agarose gel is too small to allow the efficient movement of proteins. Therefore, a poly acrylamide gel is used to separate proteins according to size
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∙ 11y agoya v cn sprte proteins from gel electrophoresis.
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What will be the voltage you have to use to run agarose gel electrophoresis for the best resolution of DNA fragments if the distance between the two electrodes is around 15cm?
888
What is the buffer solution and why is it added to the agarose?
You use a buffer when making agarose gels so that when the gel is used for electrophoresis, the gel is able to conduct electricity. The buffer contains ions from the buffer salts that will facilitate conduction. that was good
Why native gel electrophoresis can be used for determining the molecular weight of proteins?
No! native gels are used to run the proteins in native form, this will tell about the protein's mulimeric nature (ie.monomer or dimer or tetramer etc..).
Why would a scientist use a higher versus a lower percent agarose solution when preparing a gel to separate DNA?
Different percentages have different resolving powers. There is no one agarose percentage that is suitable for all sizes of DNA - you must chose the percentage best for resolving the sizes of DNA you are examining. If your agarose concentration is too dense for the size of your DNA fragments, the DNA will barely migrate through the gel. If the agarose concentration is too dilute for the size of your DNA, it will run straight through the gel without resolving into sharp bands. Generally speaking you use higher percentages if you want to resolve smaller DNA fragments and lower percentages if you want to resolve larger DNA fragments. Small DNA fragments need high percentages or else they'd run straight through the gel without being resolved into bands. Large DNA fragments need low percentages to permit them to migrate into the gel.
What is native gel electrophoresis?
Native Gel or the Native PAGE is the electrophoretic system in which the the proteins are run in their native conformation, that is that they are not denatured. This used when the function of the protein is important, especially enzymes, as the function of a protein is related to its native structure.
Function of agarose in agarose gel electrophoresis?
Agarose is used in gel electrophoresis to separate nucleic acids (like DNA) by size, charge an other physical properties. Gel electrophoresis uses an electrical current to make particles move. For example, DNA is negative, so it'll travel towards to positive electrode of the gel box. Agarose has small pores through which a DNA can travel. Bigger fragments of DNA travel shorter distances, because it takes longer for them to navigate through the pores of the agarose gel. Identically sized pieces of DNA will travel the same distance, which is why you get bands (DNA with loading dye) after you run a a gel.
What properties does gel electrophoresis separate molecules?
Gel electrophoresis is a procedure that separates molecules on the basis of their rate of movement through a gel under the influence of an electrical field. The direction of movement is affected by the charge of the molecules, and the rate of movement is affected by their size and shape, the density of the gel, and the strength of the electrical field. DNA is a negatively charged molecule, so it will move toward the positive pole of the gel when a current is applied. When DNA has been cut by restriction enzymes, the different-sized fragments will migrate at different rates. Because the smallest fragments move the most quickly, they will migrate the farthest during the time the current is on. Keep in mind that the length of each fragment is measured in number of DNA base pairs.
What will be the voltage you have to use to run agarose gel electrophoresis for the best resolution of DNA fragments if the distance between the two electrodes is around 15cm?
888
What is the buffer solution and why is it added to the agarose?
You use a buffer when making agarose gels so that when the gel is used for electrophoresis, the gel is able to conduct electricity. The buffer contains ions from the buffer salts that will facilitate conduction. that was good
Why native gel electrophoresis can be used for determining the molecular weight of proteins?
No! native gels are used to run the proteins in native form, this will tell about the protein's mulimeric nature (ie.monomer or dimer or tetramer etc..).
Why would a scientist use a higher versus a lower percent agarose solution when preparing a gel to separate DNA?
Different percentages have different resolving powers. There is no one agarose percentage that is suitable for all sizes of DNA - you must chose the percentage best for resolving the sizes of DNA you are examining. If your agarose concentration is too dense for the size of your DNA fragments, the DNA will barely migrate through the gel. If the agarose concentration is too dilute for the size of your DNA, it will run straight through the gel without resolving into sharp bands. Generally speaking you use higher percentages if you want to resolve smaller DNA fragments and lower percentages if you want to resolve larger DNA fragments. Small DNA fragments need high percentages or else they'd run straight through the gel without being resolved into bands. Large DNA fragments need low percentages to permit them to migrate into the gel.
What is used to make the DNA visible on the gel?
YES!! You can use a simple Agarose gel to separate to view the DNA on electrophoresis. Use 0.8 - 1% gel for 5-10kbp , 2% for 0.2 - 1kbp. If the fragments are really tiny, use an Acrylamide gel (vertical gel) to electrophorese and they will show right out. This is to offset the instability of high concentration gels.
What is native gel electrophoresis?
Native Gel or the Native PAGE is the electrophoretic system in which the the proteins are run in their native conformation, that is that they are not denatured. This used when the function of the protein is important, especially enzymes, as the function of a protein is related to its native structure.
Explain how an agarose gel can separate DNA fragments of different lengths.?
The separation of DNA fragments is based on size. When a DNA sample is run in a gel (electrophoresis), the lighter fragments migrate faster than the heavier (longer) fragments under the influence of an electric current. At the and of the process, the shorter fragments are found at the terminal end of the gel and the longer fragments closer to the origin
If you ran your DNA samples on a 0.8 agarose gel would you get the same results if you ran your samples on a higher percentage agarose gel?
Yes and no - it will not change the result, as such, but the resolution will be affected. The higher the density (percentage) of agarose the more it will retard your DNA sample, so larger DNA fragements run more slowly and at high percentage won't run into the gel properly. Essentially, high percentage (2%) gels are ideal for looking at small DNA fragments (100bp) and low percentage (0.7%) are for large DNA fragments (2kb). I find this webpage from Fermentas very useful for deciding what percentage to use and has lots of other useful bits on it: http://www.fermentas.com/techinfo/appendix/appendixtables1.htm#DNAMigration
What is sds-page used for?
SDS - PAGE is apparently used to seperate proteins. The proteins are by nature different sizes. SDS works as a stabilizer by separating proteins according to similar forms.
What are the steps in electrophoresis?
1) Add loading dye to desired sample(s). 2) Make a gel. Agarose gel, for example, is made by mixing agarose powder with buffer, heating until the powder has dissolved, adding ethidium bromide, pouring the mixture into a gel box, and putting in combs which are pulled out after the gel has cooled to make wells. 3) Make sure the wells are positioned so that the material that is being analyzed is has room to run. For example, since DNA is negative and runs towards to positive electrode, the wells are best off being positioned on the far negative side. 4) Add enough running buffer in the gel box to cover the gel. 5) Load sample(s) (a ladder is usually loaded as well). 6) Attach the electrodes to the power source. 7) Run for the designated amount of time. 8) After the gel has run, turn off the power source, remove the gel carefully and analyze using a UV light box.
