Final answer:
The respiratory centers in the medulla and pons, as well as the cardiovascular centers in the medulla oblongata, are the most oxygen-sensitive centers in the central nervous system, heavily influenced by chemoreceptors that monitor changes in blood gases and pH.
Step-by-step explanation:
The degree of fall in oxygen concentration necessary to abolish output from different central nervous system regulatory centers varies, with some centers being more sensitive to oxygen changes than others. Two of the most oxygen-sensitive centers in the CNS are the respiratory centers located in the medulla oblongata and pons, and the cardiovascular centers also located in the medulla oblongata. These centers are crucial in maintaining the automatic and continuous regulation of the body's respiration and blood pressure, responding to changes in carbon dioxide, oxygen, and pH levels in the blood. Chemoreceptors, both central and peripheral, play a key role in detecting these changes, and thereby mediating the appropriate reactions in these centers. An adequate blood supply to the brain is essential, and the cardiovascular system has specialized reflexes to protect this supply and ensure the CNS receives uninterrupted perfusion.