In the screening process during rDNA experiments, clones that metabolize -gal turn:
1. Colorless
2. Blue
3. Yellow
4. Green
The colonies of recombinant bacteria appear white in contrast to blue colonies of non-recombinant bacteria because of
| 1. | Non-recombinant bacteria containing -galactosidase |
| 2. | Insertional inactivation of -galactosidase in non-recombinant bacteria |
| 3. | Insertional inactivation of β-galactosidase in recombinant bacteria |
| 4. | Inactivation of glycosidase enzyme in recombinant bacteria |
How are transformants selected from nontransformants?
| 1. | Presence of more than one recognition site in the vector DNA. |
| 2. | Presence of alien DNA into the vector DNA results into insertional inactivation of selectable marker. |
| 3. | Antibiotic resistance gene gets inactivated due to insertion of alien DNA. |
| 4. | Both 2 and 3. |
Insertional inactivation of a gene helps in
| 1. | Identification of recombinant clones |
| 2. | Identification of deletion mutants |
| 3. | Identification of recombinant transformants |
| 4. | Elimination of suppression mutants |
Insertional inactivation of the lac Z gene forms-
| 1. | Blue recombinant colonies |
| 2. | Colourless recombinant colonies |
| 3. | Fluorescent green colonies |
| 4. | There is no relation between the lac Z gene and colour of the colony. |
A reporter enzyme used in biotechnology is-
| 1. | Green Fluorescent Protein |
| 2. | Luciferase |
| 3. | b Galactosidase |
| 4. | All of the above |
Which of the following would you choose as the safest and least cumbersome selectable marker-
| 1. | Ampicillin resistance gene |
| 2. | Tetracyclin resistance gene |
| 3. | Kanamycin resistance gene |
| 4. | b Galactosidase gene |
If the gene of Beta-galactosidase is not inactivated, means there will be color in the colonies of
1. Non- recombinant
2. Recombinant
3. Transformants
4. Non-transformants
Insertional inactivation results in
1. Non-recombinants
2. Recombinants
3. Transformants
4. Non- transformants
In the screening process, clones that metabolize X-gal turn
1. yellow
2. orange
3. blue
4. colorless
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