Biological Molecules.
These molecules are things like Carbohydrates, Proteins, and Lipids.
They are usually, long complex chains of molecules, made up of smaller basic units.

Carbohydrates.
Contain the element, Carbon, Hydrogen and oxygen.
Starch and glycogen are large, complex carbohydrates. Made of smaller units like glucose or maltose in long chains.

Proteins.
Contain the atoms Carbon, Hydrogen, Oxygen and Nitrogen.
Proteins are made up of long chains of amino acids.

Lipids.

Contain the elements, Carbon, Hydrogen and Oxygen.
Lipids (fats and oils) are made up of fatty acids and glycerol.

Test for Glucose.

Benedict's Reagent: if a sample is added and then heated but not boiled. A positive test for glucose will turn a coloured precipitate from blue to red, dependant on the concentration of glucose.