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Based on restriction maps of plasmid determine the number of DNA fragments and sizes of the fragments?
Plasmids are circular pieces of DNA, so the number of fragments equals the number of cuts from the restriction enzymes. You can easily see this if you start with one restriction enzyme that cuts the plasmid in only one place. Cutting the circle in one place yields you only one fragment. If the restriction cuts in two places, you end up with two fragments; with three places, three fragments, etc. With linear chromosomes, the situation is different. Cutting a linear chromosome in one place yields two fragments, cutting in two places yields three fragments, etc. So the number of fragments is always one more than the number of cuts. A restriction map of a plasmid will show all of the cuts the restriction enzymes made. Each cut is labeled with the enzyme that made it. One can count the spaces between cuts to determine the number of fragments that are produced. Restriction maps usually (but not always) also show the size of each fragment.
What else can I help you with?
What is the simple rule relating the number of fragments to the number of restriction sites presents on the linear DNA molecule?
The number of fragments generated by restriction enzyme digestion of a linear DNA molecule is equal to the number of restriction sites present plus one. This is because each restriction site results in the cutting of the DNA molecule into two fragments.
How do different restriction enzymes produce different DNA fragments from the DNA molecule?
DNA from two different people may have different sequences in the non-coding regions of their DNA. These differences may result in one person having a particular restriction site and the other person not having it. Different numbers and types of restriction sites will cause different fragments to be produced.
Why do the number of DNA fragments and the length of each fragment produced by RFLP analysis differ from person to person?
As the DNA fragments results from the action of the restriction enzymes and on the other hand mutations alter the sites where the restriction enzymes react therefore there is difference in number and of length of each fragment from person to person.
Assuming a circular piece of DNA was used as starting material how many restriction sites were there in lane three?
It takes one restriction enzyme to cut a linear piece of DNA (straight line) into two pieces. For a circular piece of DNA (plasmid), it would take two of these restriction enzymes - just think of how you would split a circle into two pieces; cutting one section will only straighten out the DNA, not split it (try cutting a rubber band for a visual).The answer to this question is completely dependent on the number of bands (representing different DNA fragment sizes) the lane produced. Since the first cut on a circular piece of DNA breaks the circle, then each consecutive cut will proceed as a linear band of DNA would.For example, if lane three produced four bands, then it took a total of three restriction enzymes (each enzyme reacting to one restriction site). Below is an example of the linear piece of DNA from lane three, with each "|" representing a restriction site. Notice how there are three restriction sites, but four fragments ("----") are produced.---- | ---- | ---- | ----As explained earlier, if a circular piece of DNA were cut to produce a linear piece like the one above, it would take one restriction site. From there, the enzymes proceed like the ones in the above example. Therefore, a circular piece of DNA that produced four bands would have used four restriction enzymes, whereas a linear piece of DNA that produced four bands would have used three restriction enzymes.
How is DNA fingerprint a specific type of restriction map?
A DNA fingerprint is a specific type of restriction map because it shows the unique pattern of DNA fragments produced by cutting DNA with restriction enzymes. This pattern is specific to an individual and can be used for identification purposes. In contrast, a traditional restriction map shows the locations of specific restriction sites along a DNA molecule.
If you took a linear piece of DNA and cut it with the restriction enzyme EcoRI and it had three restriction sites for EcoRI, how many fragments would you produce What if you had a circular piece of DNA?
If the plasmid has 3 recognition sequences for a given restriction endonuclease, then 4 linear DNA fragments are obtained because, if the DNA is linear then the number of fragments obtained is (N+1) whereas if the DNA is circular then the number of fragments obtained will be N for N recognition sequences for the given restriction endonuclease in a plasmid.
What is the simple rule relating the number of fragments to the number of restriction sites presents on the linear DNA molecule?
The number of fragments generated by restriction enzyme digestion of a linear DNA molecule is equal to the number of restriction sites present plus one. This is because each restriction site results in the cutting of the DNA molecule into two fragments.
How do different restriction enzymes produce different DNA fragments from the DNA molecule?
DNA from two different people may have different sequences in the non-coding regions of their DNA. These differences may result in one person having a particular restriction site and the other person not having it. Different numbers and types of restriction sites will cause different fragments to be produced.
How are restriction enzymes used in the laboratory?
Restriction enzymes are used to cut up DNA into fragments with 'sticky ends'. It allows for the gene of interest to be isolated. A plasmid can then also be cut with the same restriction enzyme and the sticky ends are spliced together with DNA ligase. The recombinant plasmid can then be put into new host cells via a variety of methods.
Two small restriction fragments of nearly the same?
The restriction fragments likely differ in size by a small number of base pairs, indicating a slight variation in the DNA sequence at that specific location. This could be due to a single nucleotide polymorphism (SNP) or small insertion/deletion. The differences detected in the restriction fragments can provide valuable information for genetic analysis or identification.
Why do the number of DNA fragments and the length of each fragment produced by RFLP analysis differ from person to person?
As the DNA fragments results from the action of the restriction enzymes and on the other hand mutations alter the sites where the restriction enzymes react therefore there is difference in number and of length of each fragment from person to person.
What is plasmid copy number?
The copy number reflects the average number of copies of a certain plasmid inside a host cell. The higher the copy number, the more efficient the plasmid is at replicating itself. Researchers using plasmids as vectors usually choose high copy number plasmids as their vectors since you can get a large number of plasmids from relatively fewer cells in less time.
What is a multicopy plasmid?
Every plasmid has a copy number that reflects the average number of copies of a certain plasmid inside a host cell(usually a bacterial cell). So a multicopy plasmid, exist in multiple copies in any given bacteria. It is believed that the higher the copy number is, the more efficient the plasmid is at replicating itself.
Assuming a circular piece of DNA was used as starting material how many restriction sites were there in lane three?
It takes one restriction enzyme to cut a linear piece of DNA (straight line) into two pieces. For a circular piece of DNA (plasmid), it would take two of these restriction enzymes - just think of how you would split a circle into two pieces; cutting one section will only straighten out the DNA, not split it (try cutting a rubber band for a visual).The answer to this question is completely dependent on the number of bands (representing different DNA fragment sizes) the lane produced. Since the first cut on a circular piece of DNA breaks the circle, then each consecutive cut will proceed as a linear band of DNA would.For example, if lane three produced four bands, then it took a total of three restriction enzymes (each enzyme reacting to one restriction site). Below is an example of the linear piece of DNA from lane three, with each "|" representing a restriction site. Notice how there are three restriction sites, but four fragments ("----") are produced.---- | ---- | ---- | ----As explained earlier, if a circular piece of DNA were cut to produce a linear piece like the one above, it would take one restriction site. From there, the enzymes proceed like the ones in the above example. Therefore, a circular piece of DNA that produced four bands would have used four restriction enzymes, whereas a linear piece of DNA that produced four bands would have used three restriction enzymes.
How is DNA fingerprint a specific type of restriction map?
A DNA fingerprint is a specific type of restriction map because it shows the unique pattern of DNA fragments produced by cutting DNA with restriction enzymes. This pattern is specific to an individual and can be used for identification purposes. In contrast, a traditional restriction map shows the locations of specific restriction sites along a DNA molecule.
Why might different alleles of the same gene produce different fragments when treated with the same restriction enzyme?
Well..... It is quite simple. if you take the square of the number of alleles and then times that by the smaller of the height of the triangle you should get your answer.
Why pBR322 plasmid have high copy number?
I think pBR322 has a replication module from E coli plasmid colE1 ,which permits plasmid replication even when chromosome replication and cell division are inhibited by amino acid starvation and chloramphenicol, as a result, under such condition each cell accumulates several thousands copies of the plasmids up to 3000, so that one litre of bacterial culture easily yields a milligram of plasmid DNA.
