An Hfr strain of genotype: arg- lac- leu+ strs is mated with a recipient strain of genotype: arg+ lac+ leu- strr. The strs marker is known to be transferred very late. Among the other three markers, leu+ is the last one to enter the F- cell. (Note: All bacteria have the ability to utilize 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.
Answers: 2
Biology, 21.06.2019 16:10, jroig42
Which of the following statements regarding anfinsen's denaturing experiments with ribonuclease a (rnase a) are valid? exposing the denatured protein to air oxidation and then dialysis to remove urea restored the protein to its original functionality. removing urea by dialysis and then allowing air oxidation of the denatured protein restored the protein to its original functionality. denaturing the protein with both urea and β-mercaptoethanol yielded an inactive protein. anfinsen concluded that protein folding is determined by its primary sequence.
Answers: 3
Biology, 21.06.2019 18:30, mayamabjishovrvq9
Drag each label to the correct location on the image. each label can be used more than once. a scientist introduced mutations in a gene sequence isolated from bacteria. study the sequence, and identify the steps where the mutations may affect the formation of proteins. in the sequence, black letters stand for protein coding regions and red letters stand for noncoding regions. protein will not be changed. protein may be changed. attcgtgttc atcgtgttc atcgtattc attcgtattc
Answers: 1
An Hfr strain of genotype: arg- lac- leu+ strs is mated with a recipient strain of genotype: arg+ la...
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