Translation Flashcards
what is the difference between dna and a gene?
dna is the overall blueprint for the coding of proteins where a gene is just a segment of that dna
(gene : recipe :: dna : recipe book)
define mrna
messenger; code from dna template is copied with complementary bases, resulting in single-stranded mrna
process of transcription
define rrna
ribosomal; structural component that allows for protein synthesis and assists in translation of mrna
define trna
transfer; contain a specific triplet code (anticodon) so it will carry a specific amino acid
have a CCA sequence at 3’ end where amino will attach
what is the immediate product of transcription?
pre-mrna; mrna that needs to be processed (5’ cap, poly-a tail, and spliced)
how many base pairs encode one amino acid?
triplet code; 3 bases will code for one amino acid
what are the steps of pre-mrna processing?
1.) add a modified guanine cap to the 5’ end for protection
2.) add a poly-a tail (polyadenylation) to the 3’ end for prevention of degradation
3.) splice out introns and connect exons to allow for a continuous code
what role do exons and introns play?
exons are parts of the gene that actually code for amino acids
introns are non-coding segments but allow for alternative splicing - production of multiple proteins from 1 gene
how does trna work?
has anticodon that will complement mrna at the ribosome and will add its specific amino
reaction catalyzed by aminoacyl trna synthetases (20 specific)
amino acid is activated via atp
amino then transferred to 3’ CCA and amp is released
what are the sites on a ribosome?
a site - aminoacyl; first site where amino acids enter
p site - peptidyl; holds trna + growing peptide chain
e site - exit; holds trna without the amino acid - threshold + release
EPA = 5’ - 3’ (so APE follows the 5’ - 3’ since translation follows 5’ to 3’)
what are the three stages of translation?
1.) initiation
2.) elongation
3.) termination
define initiation (for translation)
