1. Carbohydrates:

* Function: Primary source of energy for cells, structural components, and cell recognition.

* Examples: Sugars, starches, cellulose, glycogen.

2. Lipids (Fats and Oils):

* Function: Energy storage, insulation, cell membrane structure, hormone production.

* Examples: Triglycerides, phospholipids, steroids.

3. Proteins:

* Function: Structural support, enzymes (catalyze reactions), transport, defense (antibodies), signaling, movement.

* Examples: Enzymes, antibodies, collagen, hemoglobin.

4. Nucleic Acids:

* Function: Store and transmit genetic information.

* Examples: DNA (deoxyribonucleic acid), RNA (ribonucleic acid).

These four macromolecules are essential for all living organisms because they perform a wide range of functions vital for life. They are built from smaller monomers that join together to form polymers.