OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

What process occurs when simple sugars combine to form carbohydrates?

1. Hydrolysis

2. Condensation

3. Oxidation

4. Fermentation

The correct answer is: Condensation

The process where simple sugars, such as glucose or fructose, combine to form more complex carbohydrates, like disaccharides or polysaccharides, is known as condensation. During condensation, molecules come together, and a water molecule is released as a byproduct. This is a type of synthesis reaction, specifically known as a dehydration synthesis, as it involves the removal of water to bond the individual sugar molecules. In the context of biology, this is an important reaction because it allows for the formation of polysaccharides, such as starch or glycogen, which serve as essential energy storage molecules in plants and animals. The ability of simple sugars to link together into larger, more complex carbohydrate structures is foundational to cellular energy management and metabolism. Understanding condensation and its role in building larger molecules is crucial when studying biochemistry and metabolism in living organisms.