Question

23. How do genomic and cDNA libraries differ? Which can be screened with antibodies and why?

24. How are oligonucleotides, once important as probes for screening libraries, used today?

25. What is the difference between cloning and PCR?

26. Why did scientists push for the human genome to be sequenced?

Answer 1

Answer 1-
As we know that the difference b/w both of these libraries is that genomic library comprises DNA fragments which the express the entire genome of an organism while in cDNA library,
And mRNA is taken from particular cells of an organism and then cDNA consists of this mRNA in a reaction that is catalyzed by anq enzyme so genomic and cdna is differ.

Answer 2-
Suppose that you have a particular and isolated protein and also want to isolate the gene that encodes is it.
And a complete genomic λ library from mammals contains at least a million different clones cDNA library must contain as so many clones to include the sequences of scarce the m RNAs.
Then How are specific clones of interest identified in such large collection The most common method involves screening a library by hybridization with radioactively labeled RNA or DNA probes.
In the an alternative method, a specific clone in a library of cloned DNA is identified based on a some property of its encoded protein, that's all.
Answer 3-
The difference b/w PCR and Gene Cloning. Making more copies of the DNA from a single desired DNA is called DNA amplification or DNA proliferation.
and two methods have been followed to amplify the DNA. They are gene cloning and Polymerase Chain Reaction.