BIOL 112 Lecture 6: Sugars and lipids

• School: McGill University
• Department: Biology
• Course: BIOL 112
• Professor: Frieder Schoeck

Document Summary

Sugars: major categories of carbohydrates, monosaccharides, disaccharides, which consist of two monosaccharides, polysaccharides, which are composed of hundreds to hundreds of thousands of monosaccharides, basic structure (the general formula for a carbohydrate monomer is multiples of. An aldose ---- carbonyl group at end of carbon chain. A ketose ---- carbonyl group in middle of carbon chain: several hydroxyl groups. Isomers ---- same molecular formula but different structures: constitutional isomers ---- a group is attached to different carbon atoms, stereoisomers ---- a group is attached in different ways to the same carbon atom. Properties: optical isomers are mirror images of each other, optical isomers occur whenever a carbon has four different atoms or groups attached to it. E. g: glucose and galactose (different in 4" carbon atom, ring form glucoses ---- alpha glucose and beta glucose. Straight-chain glucose forms another covalent bond to become the ring firm of glucose. This coverts c-1 from a symmetric to an asymmetric carbon atom.