The compound that can give rise to glucose by gluconeogenesis is:
**Core Concept**
Gluconeogenesis is a metabolic pathway that generates glucose from non-carbohydrate sources such as amino acids, lactate, and glycerol. This process is crucial for maintaining blood glucose levels during fasting or starvation states.
**Why the Correct Answer is Right**
Pyruvate is a key intermediate in gluconeogenesis. It can be produced from various sources, including lactate, glycerol, and amino acids like alanine. Pyruvate is then converted into oxaloacetate by the enzyme pyruvate carboxylase, which is a critical step in gluconeogenesis. Oxaloacetate can then be converted into phosphoenolpyruvate (PEP), which is eventually converted into glucose through a series of reactions.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it doesn't specify a compound that can directly participate in gluconeogenesis.
**Option B:** This option is incorrect as it doesn't directly relate to gluconeogenesis.
**Option C:** This option is incorrect as it is a product of glycolysis, not a precursor for gluconeogenesis.
**Clinical Pearl / High-Yield Fact**
In critically ill patients, the administration of lactate can help promote gluconeogenesis and maintain blood glucose levels.
**Correct Answer:** C. Pyruvate