31. Two Hfr strains, Hfr-1 (arg+leu+ gal+strS) and Hfr-2 (arg+ his+ gal+ pur+ strs) were mated with a F– strain (arg–leu– gal– his–pur–strs). The results of the interrupted mating experiment […]
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![30. Four different Hfr strains of E. coli were mated with F- recipients, and the time of entry of various donor markers were found to be as below: Hfr 1: met [15 min] thr [30 min] phe [42 min] mal [57 min] Hfr 2: bio [50 min] thy [51 min] his [60 min] mal [77 min] Hfr 3: cys [10 min] phe [26 min] his [58 min] Hfr4: his [12 min] bio [22 min] azi [27 min] thi [44min] Based upon the above observations, the following statements were made assuming met to be at 0 min and thr at 15 min: (A) his is located at 59 min (B) azi is located at 74 min (C) cys is located at 11 min (D) mal is located at 76 min Which one of the following options represents all correct statements? (1) A and D only (2) B, C and D (3) A, B and C (4) C and D only](https://www.letstalkacademy.com/wp-content/uploads/2025/12/30-3.png)
CSIR NET Life Science Previous Year Questions and Solution on Genetics
Detailed Explanation of E. coli Hfr Strain Gene Mapping Using Time of Entry Data
30. Four different Hfr strains of E. coli were mated with F– recipients, and the time of entry of various donor markers were found to be as below: Hfr 1: […]
CSIR NET Life Science Previous Year Questions and Solution on Genetics
Interrupted mating mapping in E. coli
Interrupted mating experiments were performed using three different Hfr strains (1-3). The three strains have different combinations of selectable markers. The time of entry for markers for each strain is […]
CSIR NET Life Science Previous Year Questions and Solution on Genetics
Interrupted Mating Mapping in E. coli
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 […]
CSIR NET Life Science Previous Year Questions and Solution on Genetics
Interrupted Mating Mapping Problem
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 […]
CSIR NET Life Science Previous Year Questions and Solution on Genetics
Understanding Gene Distance Measurement in Bacterial Interrupted Mating Experiments
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 […]
CSIR NET Life Science Previous Year Questions and Solution on Genetics
Understanding the True Characteristics of Cells Harboring F+ Plasmid in Bacteria
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. […]
CSIR NET Life Science Previous Year Questions and Solution on Genetics
Difference Between F+ Cell and Hfr Cell in Bacterial Conjugation
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 […]
CSIR NET Life Science Previous Year Questions and Solution on Genetics
E. coli Conjugation: Cells Unable to Transfer DNA to Recipients
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’ […]
CSIR NET Life Science Previous Year Questions and Solution on Genetics
E. coli F’ gal+ bio+ Conjugation: Creating Partial Diploids for Closely Linked Genes
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 […]
