Final answer:
b. gluconeogenesis. The formation of glucose from noncarbohydrate sources is known as gluconeogenesis, a process that primarily takes place in the liver to maintain glucose levels for essential organs.
Step-by-step explanation:
The formation of glucose from noncarbohydrate sources is called gluconeogenesis. This metabolic pathway is crucial for maintaining blood glucose levels, especially during periods of fasting, starvation, or low-carbohydrate diets. Gluconeogenesis occurs primarily in the liver and, to a lesser extent, in the kidneys, providing glucose for essential organs like the brain and red blood cells that primarily rely on glucose for energy.
The other options listed, such as glycolysis, glycogenolysis, and glycogenesis, are different metabolic processes related to glucose and glycogen. Glycolysis is the breakdown of glucose into pyruvate. Glycogenolysis is the conversion of glycogen back into glucose, and glycogenesis is the formation of glycogen from glucose.