Carbohydrates (CHO) <carbons, with water attached to them (carbo-hydrate)>-carbohydrates contain only Carbon, Hydrogen and Oxygen -carbohydrates are produced in the process of photosynthesis

Carbohydrates and Energy-main energy source for living things-energy is stored for short term or long term-CHO include sugars, starches, cellulose and chitin-energy stored in chemical bonds that hold carbohydrates together-this energy is then used in any activity that the organism does

The Structure of Carbohydrates

Remember, all macromolecules are composed of monomers that join together in a deydration synthesis reaction to from polymers.

Carbohydrates

Monomer(s) PolymersMonosaccharides PolysaccharidesDisaccharides

Starch Cellulose Chitin Glycogen

Types of CHO:-CHO are classified based on the number of simple sugars that they contain and there are three types of carbohydrates according to complexityMonosaccharides -sweet tasting, simple sugars-have 6 carbon atoms and some hydroxyl groups-soluble in water (they dissolve in water)-the three most common monosaccharides are:a)Glucose (main sugar)b) Galactose (sugar found in milk)c) Fructose (sugar found in fruits)

Disaccharides/Double Sugars-consist of two monosaccharides linked together (a dehydration synthesis reaction links them together)-the hydroxyl (OH) group of glucose reacts with the hydroxyl (OH) group of fructose-soluble in water (they dissolve in water)

http://www.biotopics.co.uk/as/disaccharideformation.html-good animation of a condensation reaction

Polysaccharides (Many Sugars)(three or more monosaccharides)-macromolecules that are polymers of a few hundred/thousand monosaccharides-NOT soluble in water (do not dissolve in water)-have two important biological functions1. Energy Storage (Starch and Glycogen)2. Structural Support (Cellulose and Chitin) Glycogen

-animals store glucose in the form of glycogen in the liver and muscles to be used as quick energy-consists of hundreds of glucose molecules strung together in a highly branched chain-Starch-plants store energy in the form of starch-found in rice, wheat, potatoes, flour,-too large to be absorbed by our digestive system- we have to break them down into monosaccharides

Cellulose-a large polysaccharide found in the cell walls of plants-provides structure, protection, rigidity and support-makes up about 50% of wood*humans do not have the bacteria necessary to digest cellulose, therefore it is not a direct energy source for us, that is why we can’t eat hay-makes up wood and paper-we don’t digest it so it goes through us undigested, but it does attract water, and mucus and helps to prevent constipation. Fibre is healthy!

Chitin-makes up the exoskeleton of insects and crustaceans-tough material, we don’t digest it well-used to make contact lenses and stitches!