Which of the following describes carbohydrates?

Carbohydrates are organic molecules primarily composed of carbon, hydrogen, and oxygen, typically in a ratio of 1:2:1. This composition is fundamental to the identity of carbohydrates, distinguishing them from proteins, which are made of amino acids, and nucleic acids, which consist of nucleotides.

Carbohydrates serve several functions in living organisms, including providing energy (as in glucose), structural support (as in cellulose), and even acting as signaling molecules in certain instances. However, the defining characteristic of carbohydrates remains their specific elemental composition. This structural aspect plays a critical role in their classification and function within biological systems.