HESI A2 SCIENCE Practice Test

The four major types of macromolecules essential for life are carbohydrates, lipids, proteins, and nucleic acids. Each of these macromolecules plays a crucial role in biological processes.

Carbohydrates serve as a primary source of energy for living organisms and are involved in cell structure and recognition processes. They include sugars and starches, which provide fuel and are vital for cellular functions.

Lipids, which include fats, oils, and phospholipids, are important for storing energy, forming cell membranes, and serving as signaling molecules. Their hydrophobic nature allows them to create barriers in the form of membranes that protect cells.

Proteins are essential for a wide range of functions including catalyzing biochemical reactions as enzymes, providing structural support, and facilitating communication within and between cells. They are made up of amino acids and are vital for nearly every biological process.

Nucleic acids, which include DNA and RNA, are responsible for storing and transmitting genetic information. They play critical roles in the process of protein synthesis and are fundamental in heredity and cell division.

The other choices list various components and nutrients, but they do not encompass the full range of macromolecules essential for life. For instance, amino acids and nucleotides are building