Proteins, carbohydrates and fats are natural macromolecules. The partial structure of a protein is shown below. [Figure shows a repeating peptide linkage structure: H O H H O H H O H H | || | | || | | || | | || | N–C–C–N–C–C–N–C–C–N–C–C–N– C C C C C | | O O O O ]

1. (a)Name the linkage that joins the monomer units in a protein. [1][1]
2. (b)Name a synthetic polymer that has the same linkage as a protein. [1][1]
3. (c)Proteins are hydrolysed to give a mixture of colourless amino acids. Describe, with the aid of a labelled diagram, how paper chromatography can be used to identify the amino acids present in a mixture of amino acids. .[4][4]
4. (d)Carbohydrates can be hydrolysed. Name the class of compound formed when carbohydrates are hydrolysed. [1][1]
5. (e)(i)The diagram shows the structure of a simple fat. [Figure shows a triglyceride structure: H | H-C-O-C-C15H27 || O | H-C-O-C-C15H27 || O | H-C-O-C-C15H27 || H O ] This fat is polyunsaturated. What is the meaning of the term polyunsaturated? .[2][2]
6. (e)(ii)Describe a chemical test to show that the fat is unsaturated. name of reagent result of test ..[2][2]
7. (e)(iii)Name a synthetic macromolecule that contains the same linkage as fats. .[1][1]

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