NEW 3 Flashcards
Amino acid sequence of protein is written…
in DNA
RNA has a series of…
NONoverlapping three base “words” called codons
Transcription rewrites the DNA —> RNA, substituting..
U for T
Uracil for Thymine
A + U in RNA**
Each amino acid is…
specified by codon
__ codons are possible
64
Some amino acids have more than…
one possible codon
Genetic code decides how codons are…
translated into amino acids
Three nucleotides specify ONE…
amino acid in the genetic code
61 codons correspond…
to amino acids
AUG
- START of TRANSLATION
- codes for methionine
3 “stop” codons signal…
end of translation
Genetic Code
is universal, shared by organisms from simple to complex
RNA molecule is _______ from gene
transcribed
RNA polymerase
RNA nucleotides linked by transcription enzyme
Promoter
nucleotide sequence signal = “start transcribing”
Cap and tail of extra nucleotides are added to ends of the mRNA to…
- help RNA leave nucleus
- protect RNA from damaging enzymes
- help RIBOSOMES bind to mRNA
INITIATION
RNA polymerase CONNECTS to promoter
ELONGATION
- amino acids added ONE by ONE
- RNA grows longer
Removes introns and joins exons producing continuos coding sequence
RNA splicing
TERMINATION
- RNA polymerase reaches base in DNA template called TERMINATOR, signals the END of gene
- polymerase detaches from RNA molecule and gene
tRNA molecules
picks up _____ _____ and brings them to _______
amino acids
cytoplasm
Translation - can be divided into same…
three phases as transcription:
1 ) initiation
2) elongation
3) termination
Ribosomes are composed of…
ribosomal rRNAs and protein
Ribosomes have binding sites for…
mRNA and tRNAs