| What is a peptide bond | - A condensation reaction between amino acids - bonding them together |
| Monomers that make up proteins | - Amino acids |
| What is a dipeptide | - Two amino acids bonded together |
| What is a polypeptide | - Multiple amino acids bonded together |
| What chemical groups are the central carbon atom in an amino acid attached to | - Amino group
- Carboxyl - an acidic group
- Hydrogen atom
- R group |
| Polymerisation of amino acids meaning | - Many amino acids monomers joined together in a series of condensation reactions
- Forming a polypeptide |
| The primary structure of proteins | - The sequence of amino acids in the polypeptide chain |
| The secondary structure of proteins | - Hydrogen bonds form between the amino acids in the chain
- It either coils into an alpha helix or folds into a beta pleated sheet |
| Different bonds in the tertiary structure | - Disulfide bridges - strong not easily broken (sulfur-sulfur, covalent bonds), binds chains together
- Ionic bonds - not involved in peptide bonds - weak
- Hydrogen bonds - numerous but easily broken |
| The tertiary structure of proteins | - The chains are coiled or folded even further
- More bonds form
- Single polypeptide chained proteins form their final 3D structure at this point |
| The quaternary structure of proteins | - Some proteins are made of many polypeptide chains
- These chains are assembled again
- Forming their final 3D structure |
| Test for proteins | - Add sodium hydroxide solution - solution needs to be alkaline
- Add copper sulfate solution
- Turns purple if protein is present |
| Functions of proteins | - Enzymes
- Antibodies
- Transport proteins
- Structural proteins |
| Types of proteins | - Fibrous proteins
- Globular proteins |
| Fibrous proteins | - Insoluble
- Structural
- Many disulfide bridges
- e.g collagen |
| Globular proteins | - Soluble
- SPECIFIC 3D shape
- Metabolism
- e.g enzymes |
| Explain why differences in primary structure result in proteins with different properties | - Different sequences of amino acids
- Means bonds in different places which gives a different tertiary structure (shape) |
