Mark the correct statement for pBR322 as a plasmid
vector
I. Contains relaxed origin of replication.
II. Two genes coding for resistance to antibiotics have
been introduced.
III. There are single recognition sites for a number of
restriction enzymes at various points.
IV. Insertional inactivation is a useful selection method
for identifying recombinant vectors with insert.
1. I, II, III & IV
2. I, II only
3. II, III only
4. II only
How does a bacterial cell protect its own DNA from
restriction enzymes?
1. By adding methyl groups to adenine and
cytosines.
2. By reinforcing bacterial DNA structure with covalent
phosphodiester bonds.
3. By adding histones to protect the double-stranded
DNA.
4. By forming “sticky ends” of bacterial DNA to prevent
the enzyme from attaching
DNA fragments separated by gel electrophoresis are shown. Mark the correct statement :
1. | Band 3 contains more positively charged DNA molecules than band 1. |
2. | Band 3 indicates more charge density than bands 1 and 2. |
3. | Band 1 has longer DNA fragment than bands 2 and 3. |
4. | All bands have equal lengths and charges but differ in base composition. |
Which of the following is not a direct method of gene transfer?
1. Microinjection
2. Biolistic
3. Electroporation
4. Disarmed pathogen vector
The restriction endonuclease breaks bonds between:
1. DNA-RNA hybrid
2. Introns
3. Nucleotides, i.e., breaks the phosphodiester bond
4. Pentose sugar and nitrogenous base, i.e., breaks N-glycosidic bond
During gel electrophoresis for separation of DNA fragment:
1. Smallest fragment will move to the farthest point towards cathode
2. Smallest fragment will move to the farthest point towards anode
3. Largest fragment will move to the farthest point towards cathode
4. Largest fragment will move to the farthesr point towards anode
When we ligate a foreign DNA at the sal I site of tetracycline resistance gene in a vector pBR 322, the ____a____ plasmid will lose tetracycline resistance due to insertion of foreign DNA but can still be selected out from ____b____ ones by plating the ___c____ on ampicillin containing medium
a b c
1. Non-recombinant Recombinant Transformant
2. Recombinant Non-recombinant Transformant
3. Transformant Non-recombinant Recombinant
4. Recombinant Transformant Non-recombinant
If Pvu I restriction endonuclease is used for cleaving pBR322 cloning vector for inserting foreign DNA, which of the following can be expected in recombinants?
1. They remain resistant to tetracycline but not to ampicillin
2. They would die in tetracycline containing medium but remain alive in ampicillin containing medium
3. Replication of recombinant plasmid get prevented
4. They do not show resistance to ampicillin as well as tetracycline
If the gene of interest is cloned at ECoRI in pBR322,
the recombinant E-coli after transformation are
1. Susceptible to ampicillin and tetracyline.
2. Sensitive to tetracycline.
3. Resistant to kanamycin.
4. Resistant to ampicillin and tetracycline
Which of the following enzyme is involved in the
isolation of genetic material like DNA from a plant cell?
I. Cellulase II. Lysozyme
III. Ribonuclease IV. Protease
1. I, II, III and IV
2. I and II only
3. I only
4. I, III and IV