Flashcards in 2.3 The Genetic Code Deck (20):
What is a gene?
A section of DNA
What does each gene code for?
A specific polypeptide
What do bases code for?
What does the order of bases in a gene determine?
The order of amino acids and as a result, the type of polypeptide made
What is a codon?
A sequence of 3 bases
What else is a codon called?
A triplet or base triplet
Why is it important that different proteins have a different number and order of amino acids?
It gives them a different shape and thus allows them to carry out their function
What is each amino acid coded for by?
How many amino acids have a single codon?
Give an example of an amino acid coded for by single codon?
Methionine which is only coded for by ATG
This is the start codon
The genetic code is...
- non overlapping
What does it mean that the genetic code is degenerate? Why?
-Most amino acids have more than 1 codon
-as there are more possible combinations (64) than there are amino acids (20)
What does it mean that the genetic code is universal?
The same codons are used for the same amino acids in all living organisms
What does it mean that the genetic code is non overlapping?
Each base is only read once, no base is shared between triplets
Where are start and stop codons found?
At the beginning and end of each gene
What are the three stop codons?
What is the start codon?
What happens to the start codon later in the process of forming a polypeptide?
It is removed as it doesn't form part of the polypeptide
In what direction is he triplet code always read?
Three prime to five prime