Which organic compounds are primarily composed of carbon, hydrogen, and oxygen?

Carbohydrates are organic compounds that consist primarily of carbon, hydrogen, and oxygen. The general formula for carbohydrates often follows the ratio of 1 carbon atom to 2 hydrogen atoms and 1 oxygen atom, which can be represented as Cn(H2O)n. This structural composition gives carbohydrates their name (hydrated carbon), and it indicates a significant relationship between these elements in their molecules.

Their primary function in the diet is to provide energy, serving as a critical energy source for the body. Common examples of carbohydrates include sugars (like glucose and fructose) and polysaccharides (like starch and glycogen).

In contrast, proteins are made up of amino acids, which contain nitrogen in addition to carbon, hydrogen, and oxygen. Fats (or lipids) primarily consist of carbon and hydrogen, but they have a more complex structure, often incorporating additional elements like phosphorus in phospholipids. Vitamins comprise a range of different chemical compounds, some of which do not fit the carbon-hydrogen-oxygen framework completely and may include other elements like nitrogen or sulfur.

Thus, considering the composition and common structural characteristics of organic compounds, carbohydrates distinctly fulfill the criterion of being primarily composed of carbon, hydrogen, and oxygen.