Kaplan Nursing Entrance Practice Exam

What elements primarily make up carbohydrates?

1. Carbon, hydrogen, oxygen

2. Carbon, nitrogen, sulfur

3. Oxygen, potassium, calcium

4. Hydrogen, carbon, chlorine

The correct answer is: Carbon, hydrogen, oxygen

Carbohydrates are primarily composed of carbon, hydrogen, and oxygen. These elements form the basic structure of carbohydrates, which can be simple (like sugars) or complex (like starches and fiber). The general formula for carbohydrates can often be represented as Cn(H2O)n, indicating the presence of these three elements in a specific ratio. Understanding the composition of carbohydrates is crucial in nutrition and biochemistry, as they serve as a major source of energy for the body and play essential roles in cellular functions. The other options include elements that do not accurately characterize the composition of carbohydrates, making them unsuitable choices. For instance, nitrogen and sulfur are more relevant in the context of proteins, while potassium and calcium are minerals with different roles in the body, and chlorine is primarily associated with ionic balance and digestive processes.