What macromolecule is made up of carbon, hydrogen, and oxygen atoms and serves as a major energy source for the human body?

Carbohydrates are the macromolecules made up of carbon, hydrogen, and oxygen atoms, and they serve as a primary energy source for the human body. The chemical composition of carbohydrates typically follows the formula (CH₂O)n, indicating that for every carbon atom, there are two hydrogen atoms and one oxygen atom. This structure allows carbohydrates to be efficiently metabolized by the body for energy.

In the human diet, carbohydrates can be found in simple forms, like sugars (glucose and fructose), as well as in complex forms, such as starches and fibers. When consumed, carbohydrates are broken down into glucose, which is utilized by cells for immediate energy or stored as glycogen in the liver and muscles for later use. This makes carbohydrates essential for maintaining energy levels, especially during physical activities and proper brain function.

The other macromolecules serve different main functions in the body: proteins are primarily involved in building and repairing tissues; lipids serve primarily in storing energy and forming cellular membranes; and nucleic acids (like DNA and RNA) are responsible for genetic information storage and transfer. Therefore, carbohydrates stand out as the major macromolecule associated specifically with energy provision.