A molecule of double-stranded DNA that is 5 million base pairs long has a base composition that is 62% G + C. How many times, on average, are restriction sites for the following restriction enzymes likely to be present in this DNA molecule? a. BamHI (recognition sequence is GGATCC)

E 1 kb 1 kb DAK 6 kb Gene X E1 kb B 5 kb. Gene Z E₁kb 1 kb The figure above shows a linear chronosome containing Gene X and Gene Z and the location of sites for the restriction enzymes EcoRI (E) and BamHI (B). Refer to this map as you answer the question below. If you digest this DNA with EcoRI, then perform agarose gel electrophoresis, how many bands, and what sizes, would you expect to see? a) Two bands on the gel corresponding to the sizes 2 kb and 6 kb b) Three bands on the gel corresponding to the sizes 1 kb, 6 kb and 8 kb. c) Three bands on the gel corresponding to the sizes 1 kb, 5 kb and 6 kb d) Four bands on the gel corresponding to the sizes 1 kb, 2 kb, 5 kb and 6 kb e) Four bands on the gel corresponding to the sizes 2 kb, 3 kb, 4 kb and 8 kb

Restriction endonucleases are bacterial enzymes that cleave duplex (double-stranded) DNA at specific nucleotide sequences. The mode of replication of the animal virus SV40 has been investigated by using restriction endonucleases that cleave SV40 DNA into a number of unique segments. Like most viruses, SV40 DNA is circular. The map positions of the 11 fragments produced by a pair of restriction endonucleases are shown on the next page. Immediately following a 5 or 10 minute pulse of radioactively labeled thymidine, labeled SV40 molecules that have completed replication during the pulse are isolated. These newly replicated DNA molecules are digested by the restriction endonucleases and the resulting fragments are analyzed for the relative amounts of pulse label they contain. The results are in the table below. Assume that at the time the label was added there was a random population of replicating SV40 DNA molecules in all possible stages of synthesis. From the information given below,…

A linear DNA fragment was produced by digestion with the restriction enzyme, Xba1. This fragment with XbaI(X) sites on both ends was then further digested with HindIII (H) and EcoRI (E).  Draw a restriction map of the linear fragment based on the gel electrophoresis results shown below.  X         H         Marker             E          H/E                           __2000bp __                    __1500b                         __1300bp        __             __        __1000bp                    __                         __700bp             ­­__        __500bp                         __400bp                         __300bp                      __                         __200bp          __        __                         __100bp