Transcription Flashcards
what is transcription
synthesis of RNA using a DNA template
what is RNA?
an intermediate carrier or genetic information
what is translation
using RNA to make proteins
what is the template strand?
the DNA that is copied during the synthesis of mRNA
what is the coding strand?
the opposite strand
why is coding strand called mRNa-like strand?
sequence correspongs to the codons that are translated into proteins
be able to show bacterial genes transcription
DNA is always transcribed in which direction
3 to 5
what is open reading frame?
any sequence of bases that could encode a protein
does not contain any stop codons
what is a cistron
a segment of DNA that codes for a single polypeptide chain
encodes a protein must also be an ORF, whereas a cistron that encodes a nontranslated RNA is not an ORF
what is an operon?
bacteria cluster of related genes
what is polycistronic DNA
operons that are transcribed together to give a single mRNA
Bacterial RNA polymerase
consists fof core enzyme made of five subunits, two alpha, beta, beta’ and w and the sigma subunit
halo enzyme
core and sigma
core ensyme
two alpha, beta, beta’ and w
housekeeping sigma is called
sigma 70
what is housekeeping sigma
recognizes two special sequences of bases (-10 and -35) in the promoter region of the codiing (non-template) strand
-10 and -35 sequence are known as
promotor regions
consensus sequence
-10 is Tataat and consensus sequence is -35
what is mix and match approach
bacteria have evolved this appreach to seeting promotor strength in which the strengths of the individual promotor elements combine to determine the overall activity of the promotor
mix and match approach allows what
enables promotos to easily evolve
what are the steps of transcitpion
DNA transcribed 3 to 5’
must have primer
will have coding and RNA the same
what is a factor-independent terminator
two inverted repeats separated by several bases and followed by a run of As
how does factor-independent terminator work
hairpin.
what is used to infer evolutionary relationships?
rRNA
Why are rRNA good for phylogenetic inferences?
universally distributed
functionally constant
highly conserved
adequate length
What amplifies the 16s rRNA gene?
Standard primers
extremophiles are what
thrive in either hot or cold temperatures, or extreme salinity, alkalinity or acidity
