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28. The following table shows mapping data from three interrupted mating experiments using three different Hfr strains and an F– strain: Appearance of gene in F– cells (Time is represented […]

An interrupted mating experiment was performed between Hfr strs a+b+c+ and F– strr a–b–c– strains. The genotype of majority of streptomycin resistant (strr) exconjugant after 10,20, and 30 minutes of […]

26. The distance between bacterial genes as determined from interrupted mating experiments are measured in units of (1) cM                (2) minutes (3) bp                (4) micrometers The distance between bacterial genes […]

25. Which one of the following is true for cells harbouring F+ plasmid? (1) Their F plasmid is non-functional. (2) They exhibit increased rates of transfer of all chromosomal genes. […]

24. Which one of the following is correct statement about the difference between a F+ cell and Hfr cell? (1) In F+ cell F factor is an integral part of […]

23. Conjugation involves transfer of DNA from one cell to another. In E. coli, the cells that cannot transfer their DNA into the recipient cell are (1) Hfr           (2) F’ […]

22. In E. coli gal+ and bio+ genes are located very near to each other on genome. A bacterium with F’ gal+ on conjugation with F– can lead to diploid […]

21. Under which case of conjugation, recombination for chromosomal genes can be expected in E.coli? (1) F+ X F–             (2) F+ X HFr (3) F– X HFr           (4) F– X […]

20. Bacterial conjugation was first described by Lederberg and Tatum in 1946 as a phenomenon involving the exchange of markers between closely related strains Of Escherichia coli. For experiment they […]

19. The F+ segment of bacterta may be transferred to F bacteria by the process of (1) Conjugation             (2) Transduction (3) Transformation        (4) Fragmentation The correct answer is (1) Conjugation, […]