Answer:
B) neurons have stable, relatively unchanging internal environments.
Explanation:
Rough endoplasmic reticulum (RER) is studded with ribosomes which in turn serve as the site for protein synthesis. A cell with an extensive network of rough endoplasmic reticulum has higher rates of protein synthesis. Mitochondria are the powerhouse of cells and serve as the site for aerobic cellular respiration. A large number of ATP molecules are produced in mitochondria. Therefore, a cell with relatively many mitochondria appears to have a higher demand for ATP and higher consumption of oxygen.
A cell with higher rates of consumption of ATP and protein synthesis should be functionally active. The charge across the membrane and the internal concentration of ions such as Na+, K+ of a neuron keep on changing during the conduction of nerve impulse. Therefore, the presence of many mitochondria and RER does not indicate that the neurons maintain relatively constant internal conditions.