Which of the following enzymes is used to join bits of DNA?
Ligase
Primase
Endonuclease
DNA polymerase
A.
Ligase
Ligase is an enzyme that facilitates the joining of DNA strands together by catalyzing the formation of a phosphodiester bond.
Primase is an enzyme which is involved in the replication process of DNA. It is a type of RNA Polymerase. It catalyzes the synthesis of a short RNA segment called a primer complementary to a ssDNA template.
Nucleases are enzymes that cut, shorten or degrade nucleic acids. Endonucleases are enzymes which are able to break internal phosphodiester bonds within a DNA molecule.
DNA polymerases are enzymes that synthesize a new strand of DNA complementary to an existing DNA or RNA template.
Molecular scissors, which cut DNA at specific site is
pectinase
polymerase
restriction endonuclease
ligase
Restriction enzymes are used to cut
single stranded RNA
double stranded DNA
single stranded DNA
double stranded RNA
Restriction enzymes:
are endonucleases which cleave DNA at specific sites
make DNA complementary to an existing DNA or RNA
cut or join DNA fragments
are required in vectorless direct gene transfer.
Assertion : In recombinant DNA technology, human genes are often transferred into bacteria (prokaryotes) or yeast (eukaryote).
Reason : Both bacteria and yeast multiply very fast to form huge populations which express the desired gene.
If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion
If both Assertion and Reason are true but the Reason is not the correct explanation of the assertion
If Assertion is true but Reason is false.
If both Assertion and Reason are false
What is the first step in the Southern Blot technique
Denaturation of DNA on the gel for hybridization with specific probe
Production of a group of genetically identical cells
Digestion of DNA by restriction enzyme
Isolation of DNA from a nucleated cell such as the one from the scene of crime
Polymerase chain reaction is most useful in
DNA synthesis
DNA amplification
protein synthesis
amino acid synthesis
cDNA probes are copied from the messenger RNA molecules with the help of
restriction enzymes
reverse transcriptase
DNA polymerase
adenosine deaminase
Which one among the following is just a cloning plasmid not an expression plasmid?
pBAD-18-Cam
pBCSK
pUC18
pET
Shorter generation time of E. coli compared to eukaryotes may be explained on the basis of
shape
large surface : volume ratio
presence of cell wall
absence of organelles
