| What are proteins | They are made of long chains of amino acid. Therefore are composed of carbon, hydrogen, oxygen and nitrogen. |
| What are amino acids made of | - Amine group (NH2)
- Carboxyl group ( COOH)
- variable group (R) |
| Define dipeptide | bond formed when 2 amino acids join together |
| Define polypeptide | bond formed when more than 2 amino acids join together |
| Explain condensation reaction of polypeptides | - the carbon of one of the amino acids join withs with the nitrogen of another amino acid forming a peptide bond
- a water molecule is produced aswell |
| Define primary structure | - The sequence of amino acids in the polypeptide chain.
- held together by peptide bonds |
| Define secondary structure | Hydrogen bonds form between nearby amino acids in the chain. This makes it coil into an alpha helix or fold into a beta pleated sheet. |
| Define tertiary structure | Chain of amino acids are coiled and folded even further. More bonds form between different parts of the polypeptide chains. |
| Define quaternary structure | Proteins made of several different polypeptide chains held together by bonds. |
| What are the different types of bonds formed | - ionic bonds
- disulphide bonds
- hydrogen bonds
- london forces |
| What are gobular proteins | - round and compact
- soluble, so they're easily transported in fluids |
| Examples of gobular proteins | - Haemoglobin
- Insulin
- Amylase |
| Describe haemoglobin | - globular protein that carries oxygen around the body in red blood cells
- conjugated protein
- has a prosthetic group called haem, which contains iron which oxygen binds to.
- consists of 4 polypeptide chains |
| Define conjugated protein | A protein that has a non-protein group attached, also known as prosthetic group. |
| Describe insulin | - hormone secreted by the pancreas
- helps regulate blood glucose level
- consists of 2 polypeptide chains held together by disulphide bonds. |
| Describe amylase | - an enzyme hat catalyses the breakdown of starch in the digestive system
- made of a single chain of amino acid |
| What are fibrous proteins | - tough and rope shaped
- insolube
- structural proteins |
| Examples of fribrous proteins | - collagen
- keratin
- elastin |
| Desrcibe collagen | - found in animal connective tissue such as bone, skin and muscle
- very strong |
