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प्रश्न
Describe the role of CaCl2 in the preparation of competent cells?
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उत्तर
CaCl2 is known to increase the efficiency of DNA uptake to produce transformed bactrial cells. The divalent Ca+2 ions supposedly create transient pores on the bactrial cell wall by which the entry of foreign DNA is facilitated into the bactrial cells.
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संबंधित प्रश्न
Name the selectable markers in the cloning vector pBR322. Mention the role they play.
Draw a schematic sketch of pBR 322 plasmid and label the following in it:
(a) Any two restriction sites.
(b) Ori and rop genes.
(c) An antibiotic resistant gene.
Describe briefly the following:
Origin of replication
What is ‘Ori’ ? State its importance during cloning of a vector.
Explain the importance of ‘Selectable marker’, with the help of a suitable example.
Answer the following question.
β galactosidase enzyme is considered a better selectable marker. Justify the statement.
Answer the following question.
Expand ‘YAC’ and mention what it was used for.
The colonies of recombinant bacteria appear white in contrast to blue colonies of non-recombinant bacteria because of ______.
A clone is a ______.
Which of the following is correctly matched?
Which of the following is not a genetic vector?
Plasmid pBR322 has a PstI restriction enzyme site within gene ampR that confers ampicillin resistance. If this enzyme is used for inserting a gene for β-galactoside production and the recombinant plasmid is inserted in an E.coli strain.
What does ‘competent’ refer to in competent cells used in transformation experiments?
What modification is done on the Ti plasmid of Agrobacterium tumefaciens to convert it into a cloning vector?
Name the regions marked A, B and C.
For selection of recombinants, insertional inactivation of antibiotic marker has been superceded by insertional inactivation of a marker gene coding for a chromogenic substrate. Give reasons.
The “Ti plasmid” of Agrobacterium tumefaciens stands for ______.
