Assistant Laboratory Animal Technician (ALAT) Practice Exam

What are the two types of molecules that combine to form carbohydrates?

1. Amino acids and fatty acids

2. Proteins and lipids

3. Sugar and starch molecules

4. Vitamins and minerals

The correct answer is: Sugar and starch molecules

The combination of sugar molecules is the correct answer because carbohydrates are primarily made up of simple sugars, also known as monosaccharides (like glucose and fructose), which can join together to form more complex carbohydrates such as disaccharides (like sucrose) and polysaccharides (like starch and cellulose). When you think about starch, it’s a form of carbohydrate that consists of long chains of glucose units linked together. This demonstrates the fundamental role of sugars in the structure and function of carbohydrates. The other options do not accurately represent the building blocks of carbohydrates. Amino acids and fatty acids are the components of proteins and lipids, respectively, while vitamins and minerals play crucial but different roles in biological functions and do not form carbohydrates either. Therefore, sugar as the fundamental component highlights how carbohydrates are constructed and categorized in biological systems.