Gel electrophoresis is used to dna fragments a. separate b. join c. cut d. copy

a. separate  

Explanation:

DNA fragments are formed with the action of restriction enzymes having different sizes. The most widely used technique for separating DNA fragments is electrophoresis through agarose gels.

Agarose is a polysaccharide (such as agar and pectin) that dissolves in boiling water and then gels when it cools down like gelatin. To perform an electrophoresis, an agarose gel is prepared, DNA is introduced into small gel wells, and then an electric current is applied through the gel. Because DNA is negatively charged, it is attracted to the positive electrode. However, to reach the positive electrode, DNA must migrate through the agarose gel.

Smaller DNA fragments can migrate through an agarose gel faster than larger DNA fragments. The migration rate of linear DNA fragments through agarose is inversely proportional to log10 of their molecular weights.

Diferences: 1. eukaryotes have a nucleus, while prokaryotes do not2. eukaryotes have membrane-bound organelles, while prokaryotes do not. the organelles of eukaryotes allow them to exhibit much higher levels of intracellular division of labor than is possible in prokaryotic cells.3. eukaryotic cells are, on average, ten times the size of prokaryotic cells.4. the dna of eukaryotes is much more complex and therefore much more extnsive than the dna of prokaryotes.5. prokaryotes have a cell wall composed of peptidoglycan, a single large polymer of amino acids and sugar . many types of eukaryotic cells also have cell walls, but none made of peptidoglycan.6. the dna of prokaryotes floats freely around the cell; the dna of eukaryotes is held within its nucleus and associated with histones (proteins)7. eukaryotes undergo mitosis; prokaryotes divide by binary fission (simple cell division)