Final (ch 21) Flashcards
transcirption and translation are seperated in time and space in these but coupled in these
eukaryotes
prokaryotes
extensive processing of primary RNA transcripts in these cells
eukaryotic
T/F: RNA primer is needed for transcription
F
The nucleotide at the 5’ end of the RNA chain retains this
triphosphate
The enzyme for RNA synthesis binds to and moves along the DNA template in this direction
3’-5’
Average half life of mRNA in prokaryotes and eukaryotes
3 min
30 min
rapidly degraded by nucleases
mRNA
T/F: all genes encode proteins
F, some encode rRNA and tRNA
This drives the chain elongation
hyrdolysis of the PPi
A typical eukaryotic gen cinsits of this many exons
eight
this percent of human genome may undergo transcription to produce noncoding RNA’s
80%
T/F: the template strand is not the coding strand
T, non-template strand is the coding or sense strand
each triplet of nucleotides is called this
codon
codons for a particular protein are called this
structural gene
RNA polymerase moves this stream
downstream (+)
DNA segement going the opposite direction of the RNA polymerase
upstream (-)
Sequences immediately upstream from the start site for transcription are this
promoter
The whole unit of promoter and structural genes is called this
operon
-10 region
TATA box
-35 region
TTGACA box
RNA polymerase is this type of enzyme
processive enzyme
Promoter structure (3) going upstream in bacteria
transcription start site (0)
pribnow box (-10)
-35 region
the area from the -35 region to the TSS is this
core promoter
Stages of transcription
binding of RNA polymerase holoenzyme at promoter sites
initiation of polymerization
chain elongation
chain termination
This are base sequences that are complementary so that they can loob back on themselves and end transcription
inverted repeats
controlled by specific sequences, termination sites
intrinsic termination
second type of termination involves a special protein called
rho
T/F: RNA transcription is apparently carried out by immoble protein compleses that reel in DNA
T
In eukaryotes the key change in transpormation of silent to active chromatin is this
acetylation of histones
eukaryotic promoters have a variety of these
consensus sequences
These recognize eukaryotic promoters and unwind DNA to form a transcription bubble
transcription factors
Genes that are always transcribed
constitutive or housekeeping genes
genese that are only transcribed when needed
regulated
Operons often have to be induced by certain these
inducers
These hydrolyze lactose to free galactose and glucose
B-galactosidase
transporter for uptake of B-galactosides
lactose poermease
Number of proteins produced by the lac operon
3
t/f: operons with multiple protein-coding regions are common in prokaryotes but not eukaryotes
T
This determins the binding of CAp to the promoter of the lac operon
cAMP
The lac operon transcription is an example of this type of regulation
positive regulation
Eukaryotic mRNA recieve a 5’ this and a 3’ this
cap
poly (A) tail
