Translation

Question 1

Codon types

Answer 1

1 start codon, 3 termination codons, 60 codons for the 20 amino acids

Question 2

Define translation

Answer 2

The process by which mRNA is decoded into a protein to determine the behaviour of the organism (phenotype)

Question 3

Translation in prokaryotes

Answer 3

Begins before transcription is completed

Question 4

Translation in eukaryotes

Answer 4

Occurs in the cytoplasm

Question 5

Four components of translation

Answer 5

Ribosomes, tRNAs, activating enzymes, mRNA

Question 6

Three phases of translation

Answer 6

Initiation, elongation, termination

Question 7

Structure of the ribosome

Answer 7

Two subunits (small and large), three sites (aminoacyl-tRNA, peptidyl-tRNA, exit)

Question 8

Initiation phase

Answer 8

An initiation complex forms, consisting of initiator tRNA (methonine charged), small ribosomal subunit bound to mRNA triggers translation

Question 9

Elongation phase

Answer 9

Ribosome moves along mRNA in 5’ to 3’ direction, polypeptides grow from N to C terminus, charged tRNAs bring amino acids to ribosome sequentially

Question 10

Specificity is provided by…

Answer 10

Anticodon-codon interaction and accuracy of aminoacyl-tRNA synthases

Question 11

Polysome

Answer 11

A strand of m RNA with associated ribosomes