Rollin Hotchkiss and Julius Marmur studied transformation in the bacterium Streptococcus pneumoniae (R. D. Hotchkiss and J. Marmur. 1954. Proceedings of the National Academy of Sciences of the United States of America 40:55-60). They examined four mutations in this bacterium: penicillin resistance (P), streptomycin resistance (S), sulfanilamide resistance (F), and the ability to use mannitol (M). They extracted DNA from strains of bacteria with different combinations of different mutations and used this DNA to transform wild-type bacterial cells (P* St F* M*). The results from one of their transformation experiments are shown here. Recipient Percentage of all cells Donor Transformants DNA DNA MSF M* s* F* M* SF* 4.0 M* s* F 4.0 M S* F* 2.6 MSF* 0.41 M* SF 0.22 M S* F 0.0058 MSF 0.0071

1.) If Ethidium bromide was not added to a gel, what would happen? 2. How can you tell if an individual is heterozygous for the D1S80 marker?

Determine the coefficient of coincidence and the interference

In a three-point mapping experiment for the genes a-w-ec, the following percentages of events are observed: NCO events: 57%; SCO events between a and w: 18%; SCO events between w and ec: 22%; DCO events: 2% Assuming that w is in the middle, what is the map distance between w and ec? What is the map distance between a and w? Draw the map.

Identity gene 1 (bl, pr, vg) Identity gene 2 ( bl, pr, vg) Identity gene 3 ( bl,pr, vg) How many map units separate genes 1 and 2 ( Distance 1)? How many map units separate genes 2 and 3 ( distances 2) ?

Four Hfr strains are derived from an F+ strain of E. Coli to serve as donors for an interrupted-mating experiment. Use the time-table and partial map of the F+ strain (shown below) to determine the genes’ respective positions. Keep in mind that the map distances are NOT proportional, only the FIRST 5 markers are indicated per strain, and the entry times, recorded in minutes, are in parentheses. Transferred genes represent wild-type alleles. Based on the data, which gene can be located at position 5 on the map?

what does the Depletion of essential gene products causes spontaneous DNA damage major result mean in this experiment? (interpretation)

Can you explain a brief description of each of the methods used?

1) Using the diagram below, sketch in the pattern of bands you would expect to see after digesting the DNA of the TT, Tt and tt genotypes of the TAS2R38 gene. Use the Base Pair Standards on the left of the diagram as a reference in drawing the positions of the bands. Base Pair TASTER GENO TYPE Standards (Base Pairs) TT Tt tt 500 400 300 200 100 50

What does a recombination frequency of 50 indicate?