Questions: Which of the following is a reactant of cellular respiration? - Carbon dioxide - Nitrogen - Water - Glucose

The answer to Question 15 is the fourth one: Glucose.

Explanation for each option:

• Carbon dioxide: This is incorrect. Carbon dioxide is a product of cellular respiration, not a reactant. During cellular respiration, glucose is broken down, and carbon dioxide is released as a waste product.

• Nitrogen: This is incorrect. Nitrogen is not involved in the process of cellular respiration as a reactant. It is a major component of the atmosphere and is involved in other biological processes, such as the nitrogen cycle.

• Water: This is incorrect. Water is a product of cellular respiration, formed when oxygen combines with hydrogen ions at the end of the electron transport chain.

• Glucose: This is correct. Glucose is a primary reactant in cellular respiration. It is broken down through glycolysis, the Krebs cycle, and the electron transport chain to produce energy in the form of ATP.

In summary, glucose is the reactant in cellular respiration that is used to produce energy.