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Question 14 · A Level Edexcel Biology 1.1.13 of 4 marks
Describe how a triglyceride is synthesised from glycerol and fatty acids. (4)
A triglyceride is made when one glycerol molecule joins to three fatty acids1. Each fatty acid is attached by its own condensation reaction2, so three molecules of water are released3. The fatty acids are held to the glycerol by glycosidic bonds4.
1One glycerol reacts with three fatty acids1 mark
2Three condensation reactions, one per fatty acid1 mark
3Three water molecules are released1 mark
4Three ester bonds formGlycosidic bonds join sugars, not fatty acids.0 marks
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