Answer: Its B
Explanation:glucose as a sugar source. The alleles arg+and leu+ are necessary for synthesis of arginine and leucine respectively. The lac+ is necessary for utilization of lactose.)
Exconjugants are plated on a medium containing glucose, streptomycin, and arginine. The following results are obtained for 500 colonies isolated from these plates and tested for growth on various media:
Minimal medium (with glucose): 135 colonies
Minimal medium (without glucose) + lactose: 85 colonies
Minimal medium (without glucose) + lactose + arginine: 90 colonies
a. Write a list of possible genotypes from those 500 colonies, and indicate the number in each genotype. Show your work and circle your answer.
b. Calculate the recombination frequencies.