24 protein synthesis = translation Flashcards
what is the structure and function of the ribosome?
rRNA + protein. form a large complex with enzyme sites for protein synthesis
what is the function of tRNA?
adapters that convert DNA info to protein
what happens to the third base of a codon when binding to tRNA?
it can vary: it has “wobble” WOMP WOMP WOMP. advantage for speed and energy, fewer tRNA molecules than codons.
four fun facts about the triplet code:
degenerate, unambiguous, non-overlapping, universal
tell me about the open reading frame (ORF)
it’s the reading frame in which the codon triplets are read. any sequence of bases has 3 possible frames, the other two frames are usually non-functional and full of STOP codons
what’s the start codon?
AUG
what are the stop codons?
UAA, UAG, UGA
how big is the large subunit and what is it composed of?
50S, 36 proteins, 2 rRNA (5S, 23S)
how big is the small subunit and what is it composed of?
30S, 21 proteins, 1 rRNA (16S)
give me some fun facts about ribosomes.
15,000/cell, 1/4 of dry weight of cell, 20nm diameter
what does the ribosome do exactly?
it’s a ribozyme: rRNA has catalytic and structural function and forms major site of interaction b/w 50S and 30S
what sits at the interface between the two ribosomal subunits?
predominantly rRNA
what is splicing?
snRNA (small nuclear RNA) ribozyme activity catalyzes splicing of RNA to remove introns. in eukaryotes this is carried out by the splisosome
what does peptidyl transferase do?
rRNA ribozyme activity catalyzes peptide bond formation in protein synthesis. highly conserved base sequence.
how many different tRNAs do different species have?
40-60
