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Flashcards in RNA Synthesis Deck (35)
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1
Q
Which types of RNA are used to support protein synthesis?
A
tRNA, rRNA
2
Q
What type of RNA carries the DNA information for protein synthesis?
A
mRNA
3
Q
Where is the majority of RNA synthesis found in mammalian cells?
A
Nucleus
4
Q
3 general steps of transcription
A
Initiation, elongation, termination
5
Q
What role does RNA polymerase play in transcription?
A
"start protein" Looks for promotor sites and binds to them
6
Q
What direction does RNA synthesis proceed in?
A
5' to 3'
7
Q
What does the promotor region consist of?
A
TATA and consensus sequences
8
Q
What subunit is necessary for RNA polymerase to recognize the promotor?
A
sigma subunit
9
Q
What replaces the sigma subunit in RNA polymerase on prokaryotes?
A
Nus A Protein
10
Q
What type of DNA sequence causes termination?
A
Palindromes
11
Q
Rho factor
A
Termination factor for prokaryotes. Binds to 5' end of messages and causes termination when it catches up to the stalled ribosome
12
Q
RNA polymerase II
A
found in the nucleoplasm, does the majority of the transcription
13
Q
RNA polymerase I
A
found in the nucleolus. Produces rRNA
14
Q
RNA polymerase III
A
found in the nucleoplasm. Produces small RNA
15
Q
What is the Deadhead mushroom's effect on the body that makes it so deadly?
A
Inhibits RNA polymerase II
16
Q
What is the structure of a eukaryotic promotor?
A
TATA, CAAT (frequency of initiation), and enhancer/silencer elements (can be up or down stream)
17
Q
What is mRNA's function in prokaryotes?
A
Polycistronic message, short-lived, immediately translated
18
Q
What is mRNA's function in eukaryotes?
A
Monocistronic, introns and eons, mRNA must be processed, long-lived
19
Q
What protects the 5' end of mRNA from being degraded?
A
Caps made of methylated guanine and methylated riboses
20
Q
What are poly A tails' function?
A
Maintains message stability
21
Q
What mRNAs do NOT contain poly a tails?
A
Those coding for histones
22
Q
Introns
A
Only found in eukaryotes. Are removed during RNA processing.
23
Q
RNA splicing precursors
A
GU on 5' end, AG on 3' end
24
Q
What mediates the splicing of RNA?
A
Spliceosome
25
Q
SNRNPs
A
individual parts that form a spliceosome
26
Q
Alternative splicing
A
Exons can be spliced so they are expressed in different ways
27
Q
Wobble position of Codon
A
the third position that has less specificity when coding for an amino acid
28
Q
What are the two exceptions to the DNA codon language?
A
Mitochondria and chloroplasts
29
Q
Transition mutation
A
Purine is replaced by purine, Pyrimidine is replaced by pyrimidine
30
Q
Transversion mutation
A
Purine is changed to a pyrimidine, and vice versa
31
Q
Silent mutation
A
Codon is changes, but the amino acid is not
32
Q
Missense mutation
A
Inactive or partially active protein
33
Q
Nonsense mutation
A
nonfunctional protein
34
Q
Sickle cell anemia is caused by what mutation?
A
Missense mutation
35
Q
Frameshift mutations
A
Insertions/deletions. only have a shift if 1 or 2 bases are affected