15. SV 40 vectors, in which early region replacements are carried out, require
A.COS cell line
B.SV 40 helper virus
C.pBR 322 vector
D.none of these

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16. Cloning genes in the yeast offer which of following advantage(s)?
A.Over production of proteins of commercial value
B.Ability to glycosylate proteins during secretion
C.Ability to clone large piece of DNA
D.All of the above

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17. Which one of the following is true about Yeast Episomal plasmids (YEp) vectors?
A.Allows transformation by using crossing over
B.Has a origin of replication and rep genes
C.Carries autonomously replicating sequence
D.Carries centromere and telomere sequences

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18. Which one of the following is true about Yeast Centromeric plasmids (YCp) vectors?
A.Contains centromeric sequences
B.Segregates during meiosis and mitosis
C.Functions as true chromosome
D.All of the above

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19. Autographa California nuclear polyhedrosis virus that is used as a vector for animal cells is an example of
A.Vaccinia virus
B.Baculo virus
C.Papilloma virus
D.Retrovirus

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20. Polyhedrin protein is
A.non essential for baculo virus replication
B.major component of protein matrix in which viruses are embedded
C.both (a) and (b)
D.essential for baculo virus replication

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21. Cos cell line is
A.cohesive end site of phage λ
B.derivative of permissive CV-1 monkey cell line
C.cohesive initial site of phage λ
D.derivative of non-permissive CV-1 monkey cell line

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