Genetic Engineering Practice Test 1

1. The recognition sequence for BamHI is 5’ G|GATCC 3’. The ‘|’ represents the cutting site. What can be inferred about the ends from it?

The single stranded end is 3’ in nature

The ends created are double stranded

To decide about the nature of the ends more information is needed

The single stranded end is 5’ in nature

2. Type II cuts the sequence in the following way __________

It cuts randomly

At 100-1000 nucleotides away from the recognition sequence

Within the recognition sequence

At 27-30 nucleotides away from the recognition sequence

3. F plasmid is often used in conjugation. The correct statement is?

The factor encoded by the F plasmid is called as Filamentous (F) factor

The F plasmid encodes the factor which is transferred from one cell to another

It is transferred from one cell to another by filament

The bacteria must belong to same species to carry out the conjugation

4. How is phosphatase related to the ligation reactions?

Phosphate group is not required for the ligation reaction to take place, thus phosphatase is helpful

Phosphatases are not at all related to ligation reactions

They act as a catalyst in case of the ligation reaction

It is helpful in ceasing the unwanted ligation

5. Viral infection can also be used to take up the DNA by the cells.

True

False

6. The recognition sequence of Sau3A is 5’ |GATC 3’ and that for DpnI is 5’ GA|TC 3’. Which of the statements is true?

The ends created by Sau3A are single stranded

The ends created by both the enzymes are compatible

The ends created by both the enzymes are not-compatible

The ends created by DpnI are single stranded

7. If only one bond is broken in the sugar-phosphate backbone, it is called as ___________

leakage

break

gap

nick

8. Ligation is defined as ______________

Alignment of single stranded DNA molecules and formation of glycosidic bonds between these strands

Alignment of either of the double or single stranded DNA molecules and the formation of phosphodiester bonds. The bond can be between either one or both the strands

Alignment of only double stranded DNA molecules at the ends and the formation of phosphodiester bonds between both the strands

Alignment of either of the double or single stranded DNA molecules and formation of glycosidic bonds between both the strands

9. What is the function of methylase?

Removal of methyl groups from DNA

Both in removal and addition of methyl groups from DNA

Addition of methyl groups to DNA

It is used in production of methane gas

10. What are the effects of increasing concentration of reaction components?

It decreases chances of ligation in intramolecular and increases in that of intermolecular

It decreases chances of ligation in both types of reaction

It increases chances of ligation in both intramolecular and intermolecular reactions

It increases chances of ligation only in intermolecular and no effect on intramolecular