Question

25. Which of the following is not true concerning eukaryotic mRNA processing (A) addition of a 3' poly-A tail (D) occurs in the nucleus (C) intron splicing (B) addition of a S' cap (E) occurs in the cytoplasm 26. Which of the following is involved in maintaining lysogeny in (A) PRE (B) PRM (C) PRI (D) PRO (E) all of the choices are correct Use the following diagram to answer questions 27-28. Each circle represents a DNA molecule and the three boxes are having the identical sequences 27. This graphic represent the process of (A) recombination (B) lysogeny (C) nonreplicative transposition (D) replicative transposition 28. The solid box must represent the (A) transposon C) replicon (D) repetitive sequence plasmid (B) att site 29. Upon entry into a host cell, a retrovirus, which has a ssRNA (+) strand genome, must FIRST (A) use its genome as a mRNA to produce RNA replicase (B) use host enzyme to replicate its genome (C) synthesize a RNA strand using reverse transcriptase (D) synthesize a DNA strand using reverse transcriptase 30. All replicons must (A) have a circular nucleic acid molecule (C) have an ori (B) be composed of SSDNA only (D) carry a gene for DNA polymerase

Answer 1

Answer=

25] The following is not true concerning eukaryotic mRNA processing is

E] Occurs in cytoplasm.

explaination- A] addition of a 3' poly A tail

B] Addition of a 5'cap

c]intron splicing

d]occure in nucleus

all are the eukaryotic mRNA processing mechanisms.that takes place inside the nucleus.

because eukaryotic transcription takes place inside the nucleus,after formation of mRNA ,mRNA splicing takes place inside the nucleus.

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26] The following is involved in maintaining lysogeny in $\lambda$ phage.

E]All of the choices are correct

explaination- p_{RE ,}p_{RM ,}P_{RL ,}P_RO all are involved  in maintaining lysogeny in $\lambda$ phage.

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27]The graphic represnt the process of

B] Lysogeny

explaination- because in this representation there is integration of bacteriophage nucleic acid into the hosts bacteriums genome & formation of circular replicon in the bacterial cytoplasm.

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27]solid box must represent

c]Replicon