A-level Biology Carbohydrates and starch/sugar tests

Presentation on monosaccharides, disaccharides, polysaccharides and starch/reducing and non reducing sugar tests.

AQA A level Biology Specificaton
Unit 1 Biological Molecules

Topic:
1.1 Monomers and Polymers,
1.2 Carbohydrates

This material covers:
Monosaccharides are the monomers from which larger carbohydrates are made. Glucose, galactose and fructose are common monosaccharides.
A condensation reaction between two monosaccharides forms a glycosidic bond.
Disaccharides are formed by the condensation of two monosaccharides:
• maltose is a disaccharide formed by condensation of two glucose molecules
• sucrose is a disaccharide formed by condensation of a glucose molecule and a fructose molecule
• lactose is a disaccharide formed by condensation of a glucose molecule and a galactose molecule.
Glucose has two isomers, α-glucose and β-glucose, with structures:
Polysaccharides are formed by the condensation of many glucose
units.
• Glycogen and starch are formed by the condensation of αglucose.
• Cellulose is formed by the condensation of β-glucose.
The basic structure and functions of glycogen, starch and cellulose.
The relationship of structure to function of these substances in animal cells and plant cells.
Biochemical tests using Benedict’s solution for reducing sugars and non-reducing sugars and iodine/potassium iodide for starch.

To complete the lesson provide students with related past exam questions