Advertisements
Advertisements
प्रश्न
Describe briefly the following:
Origin of replication
Advertisements
उत्तर
One of the most important components of a plasmid is the sequence of bases that initiates replication. It is known as the origin of replication (ori). This is a region of the plasmid genome that acts as a start signal for self-replication (making another copy of itself). Any portion of DNA connected to this sequence can be replicated within host cells. This characteristic is utilised to create multiple copies of linked DNA (or DNA inserts).
APPEARS IN
संबंधित प्रश्न
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.
Can you think and answer how a reporter enzyme can be used to monitor the transformation of host cells by foreign DNA in addition to a selectable marker?
Write the role of ‘restriction sites’ in the cloning vector pBR322.
What is ‘Ori’ ? State its importance during cloning of a vector.
Answer the following question.
Expand ‘YAC’ and mention what it was used for.
How does the β-galactosidase coding sequence act as a selectable marker? Why is it a preferred selectable marker to antibiotic resistance genes? Explain.
The genetic material of virus includes:
The colonies of recombinant bacteria appear white in contrast to blue colonies of non-recombinant bacteria because of ______.
A clone is a ______.
A suitable vector for gene cloning in higher organism is ______.
Plasmids are suitable vectors for gene cloning because these ______.
A cloning vector should possess which of the following characters?
- Origin of replication (Ori)
- Ability to destroy the alien DNA
- Cloning site to link the alien DNA
- The tumour inducing plasmid Ti.
- Selectable marker.
- Low molecular weight
The CORRECT combination is
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?
For selection of recombinants, insertional inactivation of antibiotic marker has been superceded by insertional inactivation of a marker gene coding for a chromogenic substrate.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.
Describe the role of Agrobacterium tumefaciens in transforming a plant cell.
The figure below shows the structure of a plasmid.
A foreign DNA was ligated at BamH1. The transformants were then grown in a medium containing antibiotics tetracycline and ampicillin.
Choose the correct observation for the growth of bacterial colonies from the given table.
