[Campbell Biology P.232] A person consumes a diet very high in carbohydrates but low in fat.... | Practice Question

A person consumes a diet very high in carbohydrates but low in fat. Despite the low fat intake, they gain weight and store fat. Based on the provided text, which of the following best explains this phenomenon?

  • A: Excess carbohydrates are directly converted into fatty acids and then stored, a process that generates additional ATP.
  • B: The body prioritizes converting all excess nutrients, regardless of type, into fat for long-term energy storage when caloric intake exceeds demand.
  • C: Intermediates from glycolysis, such as dihydroxyacetone phosphate, can be diverted and converted into precursors for fat synthesis, consuming ATP in the process.
  • D: High carbohydrate intake inhibits fat catabolism, leading to fat accumulation even with minimal fat in the diet.

Explanation

The text explicitly states: 'an intermediate compound generated during glycolysis, dihydroxyacetone phosphate... can be converted to one of the major precursors of fats. If we eat more food than we need, we store fat even if our diet is fat-free. Metabolism is remarkably versatile and adaptable.' This process, as part of biosynthesis, consumes ATP.