What are macromolecules composed of?

Macromolecules are large, complex molecules that are crucial for various biological functions and structures. They are primarily composed of smaller subunits known as monomers. These monomers can combine in various ways to form the larger macromolecular structures. For example, proteins are made from amino acid monomers, nucleic acids like DNA and RNA are composed of nucleotide monomers, and carbohydrates are formed from sugar monomers.

The significance of this composition is that the specific order and combination of these monomers ultimately determine the properties and functions of the resulting macromolecule. Understanding this allows scientists and biologists to comprehend how macromolecules contribute to processes such as metabolism, genetics, and cell structure.

In contrast, the other choices do not provide an accurate representation of macromolecules: large proteins alone do not encompass the variety of macromolecules like carbohydrates or nucleic acids; individual atoms are too small and do not form the large structures associated with macromolecules; and fatty acids, while being components of lipids, do not represent the full range of macromolecules such as proteins, nucleic acids, and carbohydrates. Thus, identifying monomers as the building blocks of macromolecules captures the correct and comprehensive understanding of their composition.