What are not the functions of a polynucleotide kinase（）
A. Removal of the phosphate group from 5’ end
B. Removal of the phosphate group from 3’ end
C. Addition of phosphate group on 5’ end
D. Addition of phosphate group on 3’ end
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Choose the correct statement with respect to lysogen and prophage（）
A. The integrated phage is called as lysogen
B. The infected bacterial cell is called a prophage
C. If there is only growth of few lysogens, the E. coli lawn would be turbid
D. If lysogens won’t be formed, the plaques won’t be clear
Enzymes that remove nucleotides one at a time from the end of a DNA molecule are called（）
A. Ligases
B. Exonucleases
C. Endonucleases
D. Modifying enzymes
Choose the correct statement for the infectious particle of lambda phage（）
A. It is single stranded genome
B. It is circular double stranded genome
C. The ends are blunt with cos （cohesive） sequences
D. The cos （cohesive） sticking ends are created by cleavage at cos sites during phage packaging
Which of the following is correct with respect to caesium chloride centrifugation（）
A. Caesium is light in weight
B. The dissolution of caesium and nucleic acids leads to the formation of gradients
C. According to the amount of supercoiling and A+T content, the DNA settles
D. Nicked DNA settles below than supercoiled DNA
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