Biological molecules - proteins Flashcards
How is a dipeptide bond formed
When two amino acids join together
How is a polypeptide formed
When more than 2 amino acids join together
What is the general structure of an amino acids
An amino group, a carboxyl group, an R group
How are polypeptide bonds formed
Through a condensation reaction in amino acids and the bonds formed between the amino acids are called peptide bonds
What is the primary structure of proteins
The sequence of amino acids in the polypeptide chain
What is the secondary structure of proteins
H- bonds form between amino acids in the chain which makes it coil into a alpha helix/ beta pleated sheet
What is the tertiary structure
Coiling goes further , more H bonds form, ionic bonds form
Disulfide bridges form when to molecules of the amino acid of cytosine come close together
What is the quartenary structure
The way polypeptide chains are held together by bonds
How do you carry out the biuret test for proteins
Add sodium hydroxide solution then copper 2 sulphate solution- a positive test is purple, a negative test is blue
