Chapter 36: RNA Synthesis and Regulation in Bacteria (Test 1) Flashcards
1
Q
What are RNA polymerase requirements?
A
- A template
- Activated precursors in the form of the 4 ribonucleoside triphosphates
- Divalent metal ions, usually Mg2+ or Mn2+
2
Q
The template strand is known as the?
A
- Antisense strand
3
Q
The coding strand of DNA is known as the?
A
- Sense strand
4
Q
What are the 3 types of RNA?
A
- Messenger RNA (mRNA)
- Ribosomal RNA (rRNA)
- Transfer RNA (tRNA)
5
Q
What are the 3 stages of RNA synthesis?
A
- initiation
- Elongation
- Termination
6
Q
What are promoters?
A
- Specific DNA sequences that direct RNA polymerase to the proper initiation site
7
Q
In E. coli, what are the 2 DNA sequences that act as a promoter form many genes?
A
- The -10 sequence (Pribnow box)
- The -35 sequence
8
Q
About how many bases does RNA polymerase unwind from the promoter complex?
A
- 17 bases
9
Q
What is contained in the transcription bubble?
A
- RNA polymerase
- DNA
- RNA product
10
Q
How many nucleotides comprise the DNA-RNA hybrid?
A
- 8 nucleotides
11
Q
What is the simplest stop signal?
A
- The transcribed product of a segment of palindromic DNA
12
Q
What is the protein rho (ρ)?
A
- Another type of termination signal
13
Q
What does Rho do?
A
- It binds to a particular sequence on the RNA product -
- Uses the energy of ATP hydrolysis to chase down the polymerase in the transcription bubble
- Causes the bubble to dissociate
14
Q
When is the CCA sequence added to tRNA?
A
- Post-transcriptionally
