EC L1 Flashcards
In Eukaryotes where is the genetic information held?
nucleus
In eukaryotes where is the ribosomes?
cytoplasm
What carries the genetic information from the nucleus to the ribosomes?
mRNA (messenger RNA)
is RNA in cells double stranded or single stranded?
single stranded
are the number of bases in RNA equal like in DNA
No
how many BP per turn in RNA?
11
are all bp complementary or “standard’
No there are non standard pairs in golden RNA molecules
what are the three major types of RNA and what % do they count for in the body
- 5% mRNA (messenger)
- 80% rRNA (ribosomal)
- 15% tRNA (transfer)
role of mRNA?
carries genetic info copied from DNA into the cytoplasm of eukaryotic cell for translation by ribosomes
mRNA is used as a template for…?
translation by the ribosomes
rRNA in bacterial = __large and __ small
2 large and 1 small
rRNA eukaryotic = __large and __ small
2 large and 2 small
how many nucleotides long is tRNA
76 nucleotides long
what is the role of tRNA?
carry amino acids to ribosomes for use in protein synthesis
are tRNA specific in any way? if so how?
yes, each tRNA is dedicated to a specific amino acid so is proteinogenic
how many different amino acids are there?
20
differences in RNA synthesis and DNA synthesis
RNA synthesis does not have > primers > semi-conservative > nuclease activities > only one DNA strand copied
what order in prime (‘) is RNA made?
5’ to 3’
transcribed strand / template strand is what prime (‘)
3’ to 5’
non-transcribed strand / coding strand is what prime (‘)
5’ to 3’
what stand is RNA reading? template or coding?
template/transcribed
how does RNA Pol know which strand to transcribe?
promoters
how does RNA Pol know where to start?
transcribes DNA sequences that are internal on DNA molecules and not on the edges
how many DNA strands are used as a template?
one
Info card-
Only one strand of the DNA is used as a template therefore the template strand is always read 3’ to 5’ as the strands are aways anti parallel to each other
in bacteria what is the control region?
the promoter
what does RNAP do after it binds to the promoter?
opens it up and transcribes the 3’ to 5’ strand
Info card
AS RNA pol moves on the strand, the DNA is coming back together reforming the double helix.this will continue until RNA pol finishes reading the coding region of the gene. As seen below.
info card
Important note: RNA pol does not transcribe the promoter !!!! It only binds to it and it immediately starts transcribing down stream.
how do we find promoters?
footprinting
what do promoters look like?
they differ ‘consensus’ sequences
What is the consequence of primers being different from each other ?
RNA pol will recognise the promoter sequences at differential affinity.
info card
RNA does not contain equal amounts of A vs U or G vs C
info card
rRNA are Active site in ribosomes
Eukaryotes contains 4 species of rRNA
bacteria contains 3 species of rRNA
all ribosomes contain many proteins
info card on tRNA
transfer ribonucleic acid (tRNA) is a type of RNA molecule that helps decode a messenger RNA (mRNA) sequence into a protein.tRNAsfunction at specific sites in the ribosome during translation, which is a process that synthesizes a protein from an mRNA molecule.
