In the process of cellular respiration in a healthy person, what primarily happens to glucose?

• A. It is broken down to produce ATP, carbon dioxide, and water.
• B. It is excreted from the body without being metabolized.
• C. It is converted directly into proteins for muscle growth.
• D. It is stored unchanged in the liver for long-term energy.

Answer: (A)

Verified step by step guidance

1. Understand the process of cellular respiration: Cellular respiration is a metabolic pathway that converts glucose into usable energy in the form of ATP (adenosine triphosphate), while producing byproducts such as carbon dioxide and water.
2. Identify the role of glucose: Glucose is the primary molecule used in cellular respiration. It undergoes a series of chemical reactions to release energy stored in its bonds.
3. Break down the stages of cellular respiration: Glucose is metabolized through three main stages: glycolysis, the citric acid cycle (Krebs cycle), and oxidative phosphorylation. Each stage contributes to ATP production.
4. Clarify the byproducts: During cellular respiration, carbon dioxide is released as a waste product during the citric acid cycle, and water is formed during oxidative phosphorylation as electrons combine with oxygen.
5. Eliminate incorrect options: Glucose is not excreted without being metabolized, it is not directly converted into proteins, and it is not stored unchanged in the liver. Instead, it is broken down to produce ATP, carbon dioxide, and water.