Which Of The Following Chemical Equations Describes A Dehydration Reaction? Select One:
A. Monosaccharide + Monosaccharide + H2O = Disaccharide
B. Disaccharide = Monosaccharide + Monosaccharide + H2O
C. Disaccharide + H2O = Monosaccharide + Monosaccharide
D. Monosaccharide + Monosaccharide = Disaccharide + H2O
Which of the following chemical equations describes a dehydration reaction? Select one: O A. monosaccharide + monosaccharide
The Correct Answer and Explanation is:
The correct answer is:
D. Monosaccharide + Monosaccharide = Disaccharide + H₂O
A dehydration reaction, also known as a condensation reaction, is a chemical process in which two molecules are covalently bonded to each other with the removal of a water molecule (H₂O). This type of reaction is especially important in biological systems, such as the synthesis of carbohydrates, proteins, and nucleic acids.
In the context of carbohydrates, monosaccharides (simple sugars like glucose or fructose) can join together to form disaccharides (such as sucrose or lactose) through dehydration reactions. During this process, a hydroxyl group (-OH) from one monosaccharide and a hydrogen atom (H) from another are removed, releasing a water molecule (H₂O). The remaining oxygen atom forms a glycosidic bond between the two sugar molecules, resulting in a disaccharide.
Let’s analyze the given choices:
- A. Monosaccharide + Monosaccharide + H₂O = Disaccharide
→ Incorrect. This incorrectly includes water as a reactant, whereas it should be a product in a dehydration reaction. - B. Disaccharide = Monosaccharide + Monosaccharide + H₂O
→ Incorrect. This describes a hydrolysis reaction, the reverse of dehydration, where water is used to break a disaccharide into two monosaccharides. - C. Disaccharide + H₂O = Monosaccharide + Monosaccharide
→ Incorrect. This is also a hydrolysis reaction, not a dehydration reaction. - D. Monosaccharide + Monosaccharide = Disaccharide + H₂O
→ Correct. This correctly represents a dehydration reaction, where two monosaccharides combine and release a molecule of water.
Thus, option D correctly describes a dehydration reaction, a fundamental process in forming complex biomolecules.
