Living Environment Regents Practice Test

What is the primary function of carbohydrates in the human diet?

1. Store energy for later use

2. Supply energy for the body

3. Assist in digestion

4. Support immune system function

The correct answer is: Supply energy for the body

Carbohydrates serve as a primary source of energy for the body. When consumed, they are broken down into glucose, which can be used immediately for energy or stored for future use. This energy is essential for all bodily functions, including physical activity and maintaining metabolic processes. While carbohydrates can also contribute to energy storage in the form of glycogen in the liver and muscles, their main role is to provide fuel that the body can readily access. Considering the other options, storing energy for later use is more specific to the function of certain carbohydrates like glycogen, rather than their overarching role in the diet. Assistance in digestion typically relates to dietary fiber, a type of carbohydrate, but it is not the primary function of carbohydrates overall. Supporting immune system function is primarily the role of proteins and certain vitamins and minerals, rather than carbohydrates. Thus, the most accurate description of carbohydrates' primary role in the human diet is that they supply energy for the body.