2.1.3 Simple Sugars

Carbohydrates in living organisms:

Carbohydrates make up about 10% of the organic matter of a cell. The functions of carbohydrates in organisms include:

·         energy source- released from glucose during respiration

·         energy store- e.g. starch

·         structure- e.g. cellulose

Some carbs also form part of larger molecules (e.g. nucleic acids, glycolipids).

Carbs contain the elements C, H and O. The term carbohydrate essentially means hydrated carbon, because the elements are found in the proportions C_n(H₂O)_n.

 Simple Sugars:

The simplest carbohydrates are called monosaccharides. These are the monomers (basic units) of carbohydrates. All larger carbs are made by joining monosaccharide’s together.

There are a number of diff. monosaccharide’s; containing between 3-6 carbon atoms. All have very similar properties:

·         soluble in water

·         sweet tasting

·         form crystals

The monosaccharides are grouped according to the no. of carbon atoms in the molecule:

·         3-carbon monosaccharide = triose sugars

·         5-carbon atoms monosaccharide = pentose sugars

·         6-carbon monosaccharide = hexose sugars.

The most…