Carbohydrates and Lipids

Carbohydrates elements

carbon, hydrogen, oxygen (1:2:1)

Monosaccharides general formula

(CH2O)n

Alpha glucose

Beta glucose

Galactose

Diasaccharide reaction

Condensation reaction between two monosaccharides to form a glycosidic bond. Molecule of water is released.

Sucrose

made up of a-glucose and fructose

Lactose

made up of glucose and galactose

Maltose

made up of two glucose molecules

Test for reducing sugars

Benedict's test. A blue solution, add a few drops to your solution. Heat in a water bath and if reducing sugars are present the benedict's will turn brick red. Happens because reducing sugars reduce the copper(II) ions in Benedict's solution to copper(I) ions.

Test for non-reducing sugars

Heat with HCL then neutralise with sodium hydrogen carbonate, which produces monosaccharides needed to conduct a test with Benedict's solution.

What are reducing sugars?

All monosaccharides and some disaccharides (not sucrose)

process that splits glycosidic bonds

hydrolysis. Water is added

Starch compounds

amylose and amylopectin

Amylose structure

• Linear polysaccharide

• alpha 1-4 glycosidic bonds

Properties of amylose

• Large surface area

• Insoluble

Amylose function

• Energy store

• Provides structural stability

• Used for slow release of glucose

Amylopectin structure

Branched Chains of alpha glucose 1-4 and 1-6 glycosidic bonds

Properties of amylopectin

• More soluble in water than amylose

• Digested more quickly

Functions of amylopectin

Branches of glucose are broken off for quick release of glucose when more energy is needed

Glycogen structure

• Branches have alpha(1,6) bonds which can be broken off for quick release of glucose Linkages have alpha(1,4) bonds.

• Compact

lipid structure

glycerol and 3 fatty acids (triglyceride) combined using ester bonds

difference between fats and oils

Fats are solid at room temperature and oils are liquid at room temperature

glycerol chemical formula

C3H8O3

saturated fatty acid

Fatty acid with no carbon-carbon double bonds.

unsaturated fatty acid

Fatty acid with one or more carbon-carbon double bonds.

Ester bond

formed in condensation reaction between carboxyl (-COOH) of fatty acid and hydroxyl group (-OH) of glycerol called esterification