I would really appreciate if there could be an explanation for the correct answe
ID: 58161 • Letter: I
Question
I would really appreciate if there could be an explanation for the correct answer. Thank you so much!
1. Which of the following distinguishes the sequences and function of prokaryotic from eukaryotic promoters?
Only prokaryotic promoters contain conserved sequences
Only eukaryotic promoters contain conserved sequences
Only in eukaryotes are accessory proteins required for binding of RNA polymerase
Only in prokaryotes are accessory proteins required for binding of RNA polymerase
None of the above
Answers (1) and (4)
Answers (2) and (3)
2. Amongst RNAs, which of the following RNA types found in cells are relatively unstable?
mRNA
rRNA
tRNA
snRNA
All are equally unstable
Answers (2) and 3)
Answers (2), (3), and (4)
3. What is relationship between poly (A) tail length and mRNA translation in eukaryotes?
There is no relationship
Poly (A) tails are involved in binding of mRNA to the tRNAs
Long poly (A) tails impart shortened translation to mRNAs
Long poly (A) tails impart lengthened translation to mRNAs
There are no poly (A) tails in eukaryotic mRNAs, they are only in prokaryotic mRNAs
4. Small nuclear RNAs (snRNAs) play a role in which of the following processes?
DNA replication functioning as primers
RNA synthesis functioning as transcription initiation factors
RNA processing functioning as catalysts of intron removal
Translation by linking the mRNA with the ribosome
Addition of the 5’-7-methylguanine (CAP)
5. What is the role of sigma protein in mRNA synthesis in prokaryotes?
Forms the primer for mRNA synthesis
Termination of mRNA synthesis
Binding of RNA polymerase to promoters
Forming stem-loop structures in mRNA
Degradation of mRNA
Protection of mRNA from degradation
None of the above, sigma protein has no role in mRNA synthesis
Explanation / Answer
1. The correct option E. None of the above
Both the prokaryotes and eukaryotes contain conserved sequences, and need accessory proteins required for binding of RNA polymerase.
2. snRNAs are the most unstable RNA types found in cells.
Hence, the correct option is snRNA.
3. There is actually no relationship between poly A tail length and mRNA translation.
Hence, the correct option is There is no relationship.
4. snRNAs are involved in RNA processing.
Hence, the correct option is RNA processing functioning as catalysts of intron removal.
5. Sigma protein promotes the binding of RNA polymerase to mRNA.
Hence, the correct option is Binding of RNA polymerase to promoters