What type of macromolecule contains atoms of carbon, hydrogen, and oxygen in a 1:2:1 ratio?

Carbohydrates are the type of macromolecule that consist of carbon, hydrogen, and oxygen in a specific 1:2:1 ratio. This composition is a defining characteristic of carbohydrates, which typically have the general formula (C_n(H_2O)n). For example, glucose, a simple sugar, has the formula (C_6H{12}O_6). In this structure, there are six carbon atoms, twelve hydrogen atoms, and six oxygen atoms, clearly illustrating the 1:2:1 ratio of carbon to hydrogen to oxygen.

This unique structure of carbohydrates allows them to play crucial roles in biological functions, such as providing energy, serving as structural components in cells, and participating in cellular signaling. The other types of macromolecules mentioned do not possess this specific atomic ratio: proteins are made up of amino acids containing nitrogen in addition to carbon, hydrogen, and oxygen; nucleic acids consist of nucleotides that include phosphate groups; and lipids, which primarily contain carbon and hydrogen, do not follow the carbohydrate's ratio pattern and are generally hydrophobic. Understanding these distinctions helps clarify why carbohydrates are characterized by this particular atomic ratio.