What process involves making glucose from non-carbohydrate sources?

• A. Glycogenesis
• B. Glycogenolysis
• C. Gluconeogenesis
• D. Fermentation

Answer: (C)

The process of making glucose from non-carbohydrate sources is known as gluconeogenesis. This metabolic pathway is crucial for maintaining blood glucose levels during periods of fasting, intense exercise, or when dietary carbohydrates are scarce. It allows the body to synthesize glucose from precursors such as amino acids (especially alanine), lactate, and glycerol, thus ensuring that vital organs, particularly the brain and red blood cells, have a continuous supply of this essential energy source.

In contrast, glycogenesis is the process of converting glucose into glycogen for storage, primarily in the liver and muscles. Glycogenolysis refers to the breakdown of glycogen back into glucose when energy is needed. Fermentation is a metabolic process that converts sugars into acids, gases, or alcohol, primarily used by certain microorganisms in anaerobic conditions. Each of these processes serves different physiological functions related to energy storage and utilization, but gluconeogenesis specifically addresses the synthesis of glucose from non-carbohydrate substrates, making it the correct answer in this context.