REGISTERED NURSE ASSISTANT AT SURGERY – CERTIFIED
(RNAS-C) | QUESTIONS & ANSWERS | NEW 2026/2027 UPDATE |
GRADED A+| 100% CORRECT (VERIFIED SOLUTIONS)
Important note about RNA processing -
CORRECT|ANSWER
All eukaryotic RNAs processed, coding or not (mRNA, lncRNA, siRNA, etc.)
à all RNAs processed EXCEPT for bacterial RNAs
How is the 5' end of a pre-tRNA processed? -
CORRECT|ANSWER
cleavage by an enzyme called RNase P
RNase P is a ribozyme; an enzyme where the RNA instead of protein is reposible for catalyitic activity
What are RNase P -
CORRECT|ANSWER
· RNase P consists of RNA and protein molecules
ribozyme
involved in tRNA processing:
catalyses cleavage of the 5' end of pre-tRNA
Key takeaway:
Cleavage of pre-tRNA's are catalyzed by -
CORRECT|ANSWER
ribozymes
Note: don't confuse RNase P by with snoRNA -
CORRECT|ANSWER
, Note that this is fundamentally different from the role of snoRNAs in snoRNPs, in which the reaction
is catalyzed by protein com-ponents of the ribonucleoprotein complex.
How is the 3' end of tRNA's generated? -
CORRECT|ANSWER
conventional protein Rnase (ribonculease enzyme)
it adds a CCA terminus
Why do all tRNA's have the sequence CCA at their 3' ends? -
CORRECT|ANSWER
o This sequence is the site of amino acid attachment, so it is required for tRNA function during
protein synthesis.
Key notion: Processing of tRNAs involves addition of a CCA 3′ terminus and extensive base
modification. -
CORRECT|ANSWER
Figure 8.13 Processing of transfer RNAs -
CORRECT|ANSWER
Transfer RNAs are derived from pre-tRNAs, some of which contain several individual tRNA
molecules.
· Cleavage at the 5′ end of the tRNA is catalyzed by the RNase P ribozyme;
· cleavage at the 3′ end is catalyzed by a conventional protein RNase.
· A CCA terminus is then added to the 3′ end of many tRNAs in a post-transcriptional processing step.
· Finally, some bases are modified at characteristic positions in the tRNA molecule.
Why are some tRNA contain modified bases? -
, CORRECT|ANSWER
· Modification alters base-pairing/coding properties
Clevage during tRNA processing -
CORRECT|ANSWER
5' end à Ribozyme (RNA)
3'end à conventional RNase (protein)
What to know about tRNA processing -
CORRECT|ANSWER
2 Processing events
1)Cleavage
2)Base modification
1. cleavage
@ 5' end: Ribozyme (RNA w/ catalytic activity), called RNase P, cleaves tRNA
@ 3' end: Ribonuclease, RNase, cleaves tRNA
2. Base modification
Anticodon bases, and nearby bases, can be modified
(Don't need to memorize modifications)
why are tRNA's cleaved during their processing -
CORRECT|ANSWER
More RNA transcribed than actually needed for tRNA to function, so trim it:
When are mRNA processed in eukaryotes? -
CORRECT|ANSWER
in the nucleus
(RNAS-C) | QUESTIONS & ANSWERS | NEW 2026/2027 UPDATE |
GRADED A+| 100% CORRECT (VERIFIED SOLUTIONS)
Important note about RNA processing -
CORRECT|ANSWER
All eukaryotic RNAs processed, coding or not (mRNA, lncRNA, siRNA, etc.)
à all RNAs processed EXCEPT for bacterial RNAs
How is the 5' end of a pre-tRNA processed? -
CORRECT|ANSWER
cleavage by an enzyme called RNase P
RNase P is a ribozyme; an enzyme where the RNA instead of protein is reposible for catalyitic activity
What are RNase P -
CORRECT|ANSWER
· RNase P consists of RNA and protein molecules
ribozyme
involved in tRNA processing:
catalyses cleavage of the 5' end of pre-tRNA
Key takeaway:
Cleavage of pre-tRNA's are catalyzed by -
CORRECT|ANSWER
ribozymes
Note: don't confuse RNase P by with snoRNA -
CORRECT|ANSWER
, Note that this is fundamentally different from the role of snoRNAs in snoRNPs, in which the reaction
is catalyzed by protein com-ponents of the ribonucleoprotein complex.
How is the 3' end of tRNA's generated? -
CORRECT|ANSWER
conventional protein Rnase (ribonculease enzyme)
it adds a CCA terminus
Why do all tRNA's have the sequence CCA at their 3' ends? -
CORRECT|ANSWER
o This sequence is the site of amino acid attachment, so it is required for tRNA function during
protein synthesis.
Key notion: Processing of tRNAs involves addition of a CCA 3′ terminus and extensive base
modification. -
CORRECT|ANSWER
Figure 8.13 Processing of transfer RNAs -
CORRECT|ANSWER
Transfer RNAs are derived from pre-tRNAs, some of which contain several individual tRNA
molecules.
· Cleavage at the 5′ end of the tRNA is catalyzed by the RNase P ribozyme;
· cleavage at the 3′ end is catalyzed by a conventional protein RNase.
· A CCA terminus is then added to the 3′ end of many tRNAs in a post-transcriptional processing step.
· Finally, some bases are modified at characteristic positions in the tRNA molecule.
Why are some tRNA contain modified bases? -
, CORRECT|ANSWER
· Modification alters base-pairing/coding properties
Clevage during tRNA processing -
CORRECT|ANSWER
5' end à Ribozyme (RNA)
3'end à conventional RNase (protein)
What to know about tRNA processing -
CORRECT|ANSWER
2 Processing events
1)Cleavage
2)Base modification
1. cleavage
@ 5' end: Ribozyme (RNA w/ catalytic activity), called RNase P, cleaves tRNA
@ 3' end: Ribonuclease, RNase, cleaves tRNA
2. Base modification
Anticodon bases, and nearby bases, can be modified
(Don't need to memorize modifications)
why are tRNA's cleaved during their processing -
CORRECT|ANSWER
More RNA transcribed than actually needed for tRNA to function, so trim it:
When are mRNA processed in eukaryotes? -
CORRECT|ANSWER
in the nucleus
