Rna Synthesis And The Genetic Code
Compiled By Simon Mwangi
Edition: 2024/25
, Science | Biochemistry I of V pages
1. mRNA carries the information encoded in the DNA to the ___ where it is ____ into proteins
cytoplasm; translated
2. tRNAs serve as ___ for AAs
carriers
3. rRNA is a major component of the protein synthesizing machinery, the ____
ribosome
4. All RNAs are synthesized by RNA polymerases in the ____. An exception to this is the small percentage of
nucleus; mitochondria
5. True or false? All three classes of RNA require processing of the initial product of transcription to yield a
true
note: processing occurs in nucleus
6. Bacteria contains about ____ genes and man perhaps ____ genes.
2000; 25000
7. What are the 5 steps in transcription?
location of the segment of DNA to be transcribed (formation of open-promoter complex)
synthesis of RNA
termination of synthesis
processing of the primary transcript
prokaryotic vs. eukaryotic
8. Upstream from the transcription start site are sequences of nucleotides called ____ sequences that signal
consensus; promoter
9. Binding of RNA polymerase to the promoter region causes localized unwinding of the DNA template called
open
10. RNA polymerase is a huge protein, about _____ kDa
500,000
11. RNA synthesis, as with DNA synthesis, proceeds in what direction?
5 to 3
12. The RNA polymerase moves along the surface of the DNA in a processive manner. What does this mean?
it stays attached throughout synthesis and elongates the RNA transcript
13. For each of the following RNA polymerase subunits, give its role:BetaBetasigma
Beta: active enzyme siteBeta: important for binding to DNAsigma: required to recognize and bind to the
14. In regards to the promoter region, 10 residues upstream from the transcription start site is a region known
TATA; A; T
Biochemistry 2024/25 Edition