Proteins Flashcards
What elements do proteins contain?
- Carbon, hydrogen, oxygen, nitrogen
How many different amino acids are there?
- 20 different amino acids
What is the structure of a single amino acids?
- variable group
- amine group
- carboxyl group
What type of reactions do amino acids join by?
- condensation reactions
What happens when two amino acids join?
- forms a dipeptide
What happens when many amino acids join together?
- polypeptide
What bonds do amino acids form?
- peptide
What is the primary structure of proteins?
- The precise number and sequence of amino acids in the polypeptide chain
- only bonds present are peptide bonds
What is the secondary structure of proteins?
- The hydrogen/oxygen/nitrogen atoms in the polypeptide primary structure interact to form hydrogen binds
- hydrogen bonds form various points along the polypeptide chain, pulling the chain into arranged shapes - alpha helix or beta pleated sheet
What is the tertiary structure of proteins?
- This is how the protein folds up into its specific 3D shape
- Hydrogen Bonds (weakest)
- Ionic bonds
- Disulphide bonds (strongest)
When do Hydrogen bonds form?
- forms when there is two R groups close together with a slightly positive and negative atom
When do Ionic Bonds form?
- forms when oppositely charged R groups are positioned close together in the amino acid chain.
When do Disulphide bonds form?
Forms whenever there are 2 cystine amino acids together - The R groups contain sulfur, creates a strong bond
What is the Quaternary structure of proteins?
- several polypetide join together
- held together by the same bonds as the tertiary structure
What is the structure of collagen?
long, rigid structure in which three polypetides are wound around one another in a rope like triple helix
