Final answer:
Glucose is the body's most readily available source of energy, but red blood cells do not use it as their primary source of energy.
Step-by-step explanation:
In which of the following blood glucose is not a primary source of energy? A) Red Blood Cells B) Brain C) Central Nervous System D) Blood Heat Regulation
Glucose is the body's most readily available source of energy. The brain primarily relies on glucose as its main fuel source. However, Red Blood Cells do not use glucose as a primary source of energy. Unlike most other cells in the body, red blood cells do not have mitochondria and cannot perform aerobic respiration. Instead, they rely on glycolysis to generate ATP without using glucose as an energy source.