Translation Flashcards
What is a proteome?
The entire complement of proteins that can be expressed from a genome
What is a codon?
A group of 3 bases that code for a particular amino acid.
Why is the genetic code described as degenerate?
Each amino acid may be coded by more than one codon
What are ribosomes made out of?
Ribosomal RNA and some proteins
Where are ribosomes found?
free in the cytoplasm or bound to the endoplasmic reticulum
What is the structure of tRNA?
A short single strand of RNA which is folded into a clover leaf and held together by hydrogen bonds. Has an amino binding site which are 3 exposed bases and an anticodon binding site. This is a series of 3 bases which are complementary to the codon on the mRNA which coded for the amino acid that tRNA carries
What is translation?
The mRNA is read by a ribosome and the code is translated into a polypeptide chain
What is the 1st stage of Translation?
A ribosome is attached to the start codon on the mRNA and a tRNA with a complementary anticodon to the start codon binds to the mRNA. Methionine is the specific amino acid attached.
What is the 2nd stage of Translation?
The ribosome moves along to the next codon and the process is repeated. The enzyme catalyses the condensation reaction between amino acids to join them wit a peptide bond. This forms a polypeptide.
What is the 3rd stage of Translation?
The ribosome continues to move along the mRNA and tRNAs arrive with amino acids at each codon until the stop codon. The components separate and the polypeptide is complete.
What is Mutation?
A change to the DNA base sequence.
What happens to the protein if a mutation occurs?
The primary structure could change
What happens if a base is changed in a codon?
It codes for a different amino acid, the sequence of amino acids would be altered and the protein made could be different or damaged
