Question

What are the the functional groups for carbohydrates, lipids and proteins?

Answer 1

See below.

Explanation:

Carbohydrates have the formula `C_x(H_2O)_y` and contain the ether linkage C—O—C aka the glycosidic linkage.

Proteins are polyamides containing the functional group CONH, i.e. the amide linkage

Lipids are very broad and it depends on the molecule you are looking at.
For example, glycerol is a lipid and it contains the hydroxide (OH) functional group. Stearic acid is another example but it contains the carboxyl (COOH) functional group.

But the functional groups on lipids are usually COOH and OH.