Advertisements
Advertisements
प्रश्न
Restriction enzymes should not have more than one site of action in the cloning site of a vector. Comment.
Restriction enzymes present in the cloning site of a vector should not have more than one recognition site. Comment.
Advertisements
उत्तर
If the restriction enzymes have more than one recognition site in a vector then the vector itself will get fragmented on treatment with the restriction enzyme.
APPEARS IN
संबंधित प्रश्न
Explain with the help of a suitable example the naming of a restriction endonuclease.
Suggest a technique to a researcher who needs to separate fragments of DNA.
Name the enzymes that are used for the isolation of DNA from bacterial and fungal cells for recombinant DNA technology.
Make a chart (with diagrammatic representation) showing a restriction enzyme, the substrate DNA on which it acts, the site at which it cuts DNA and the product it produces.
Explain briefly:
Restriction enzymes and DNA
Give a reason why :
Single cloning site is preferred in a vector.
The total number of nucleotide sequences of DNA that code for a hormone is 1530. The proportion of different bases in the sequence is found to be Adenine = 34%, Guanine = 19%, Cytosine = 23%, Thymine = 19%.
Applying Chargaff’s rule, what conclusion can be drawn?
Molecular scissors, which cut DNA at specific site is ______.
'Restriction' in restriction enzyme refers to
DNA fragments separate according to size through?
DNA strands on a gel stained with ethidium bromide when viewed under UV radiation, appear as ______
'Restriction' in Restriction enzyme refers to ______.
While isolating DNA from bacteria, which of the following enzymes is not required?
Which of the following bacteria is not a source of restriction endonuclease?
Which of the following statements does not hold true for restriction enzyme?
Restriction enzymes that are used in the construction of recombinant DNA are endonucleases which cut the DNA at ‘specific-recognition sequence’. What would be the disadvantage if they do not cut the DNA at specific-recognition sequence?
A mixture of fragmented DNA was electrophoresed in an agarose gel. After staining the gel with ethidium bromide, no DNA bands were observed. What could be the reason?
CTTAAG
GAATTC
- What are such sequences called? Name the enzyme used that recognizes such nucleotide sequences.
- What is their significance in biotechnology?
Carefully observe the given picture. A mixture of DNA with fragments ranging from 200 base pairs to 2500 base pairs was electrophoresed on agarose gel with the following arrangement.
(a) What result will be obtained on staining with ethidium bromide? Explain with reason.
(b) The above setup was modified and a band with 250 base pairs was obtained at X.
What change(s) were made to the previous design to obtain a band at X? Why did the band appear at position X?
Given below is the stepwise schematic representation of the process of electrophoresis. Identify the 'alphabets' representing
- Anode end
- smallest/lightest DNA strand in the matrix
- Agarose gel
State the importance of elution in this process.
'EcoRI' has played a very significant role in rDNA technology.
- Explain the convention for naming EcoRI.
- Write the recognition site and the cleavage sites of this restriction endonuclease.
State the principle involved in separation of DNA fragments using gel electrophoresis.
How are DNA fragments visualised once they are separated by gel electrophoresis?
