BSCI330 the central dogma - translation Flashcards
where is genetic info stored
in chromosomes in the nucleus
when can mRNA be translated
once mature and in the cytosol
what is translation
RNA -> protein
no 1 to 1 correspondence: 20 amino acids, but only 4 bases
how many combinations are possible with nucleotides
64
for a given protein sequence can there be more than one RNA sequnece
yes
what does transfer RNA do
tRNA matches amino acids with codons
what does each tRNA contain
a loop with a complementary 3 nucleotide sequence called an anticodon
(UUU -> AAA = anticodon)
how is amino acid coupled to tRNA
aminoacyl-tRNA synthetase
when is amino acid first activated
by attaching to AMP, creating high energy bond, then is transferred to tRNA
what does synthetase do
proofreads for accuracy
what direction does protein synthesis occur in
N-terminal -> C-terminal
how is polypeptide chain extended
growing polypeptide chain remains attached to tRNA; new aminoacyl tRNA replaces old tRNA
what decodes the RNA message
ribosome
what is the ribosomes structural and catalytic core
ribozyme
what does translation begin with
AUG (Met), which uses an initiator tRNA
