Which of the following statements about human metabolism is correct?

• A. Metabolism is not influenced by factors such as age, diet, or physical activity.
• B. A person's metabolism remains constant throughout life.
• C. Metabolism increases steadily as a person gets older.
• D. Metabolism typically decreases with age due to changes in muscle mass and activity levels.

Answer: (D)

Verified step by step guidance

1. Understand the concept of metabolism: Metabolism refers to the chemical processes that occur within a living organism to maintain life, including the breakdown of food for energy and the synthesis of molecules needed for growth and repair.
2. Recognize the factors that influence metabolism: Metabolism is affected by various factors such as age, diet, physical activity, muscle mass, and hormonal changes.
3. Analyze the relationship between age and metabolism: As people age, their muscle mass tends to decrease, and physical activity levels may decline. This leads to a reduction in the basal metabolic rate (BMR), which is the energy required to maintain basic bodily functions at rest.
4. Evaluate the incorrect statements: The first statement is incorrect because metabolism is influenced by factors like age, diet, and physical activity. The second statement is incorrect because metabolism does not remain constant throughout life. The third statement is incorrect because metabolism does not increase steadily with age; it typically decreases.
5. Conclude with the correct statement: The correct answer is that metabolism typically decreases with age due to changes in muscle mass and activity levels, which aligns with the biological understanding of metabolic processes.