What are the four main types of macromolecules in biology?

The four main types of macromolecules in biology are proteins, nucleic acids, carbohydrates, and lipids, which play crucial roles in various biological processes.

Proteins are essential for numerous functions, including acting as enzymes that catalyze biochemical reactions, serving structural roles in cells, and playing a part in immune responses. They are made up of amino acids and fold into specific three-dimensional shapes that determine their function.

Nucleic acids, which include DNA and RNA, are responsible for storing and transmitting genetic information. DNA carries the instructions for life, while RNA is involved in protein synthesis and other cellular activities.

Carbohydrates serve as energy sources and structural components. They are composed of sugar molecules and are important for energy storage (like glycogen in animals and starch in plants) and the formation of cellular structures (such as cellulose in plant cell walls).

Lipids are diverse molecules that are hydrophobic or amphiphilic in nature. They include fats, oils, and phospholipids, which are vital for forming cell membranes, storing energy, and acting as signaling molecules.

Each of these macromolecules contributes to the structure and function of living organisms, making option A the correct choice. The other options either mix different categories or focus on