Kaplan Nursing Entrance Practice Exam

What is the function of the receptors in the medulla oblongata?

1. Detect oxygen levels in the bloodstream

2. Monitor blood glucose levels

3. Regulate electrolyte balance

4. Control skeletal muscle movement

The correct answer is: Detect oxygen levels in the bloodstream

The function of the receptors in the medulla oblongata is primarily to detect oxygen levels in the bloodstream. These receptors are part of the body's homeostatic mechanisms, specifically related to the regulation of respiratory function. The medulla oblongata contains chemoreceptors that are sensitive to changes in blood chemistry, particularly the levels of carbon dioxide and oxygen. When oxygen levels in the blood decrease, the receptors send signals to the respiratory centers in the brain, prompting an increase in the rate and depth of breathing to enhance oxygen intake and expel carbon dioxide. In terms of other functions, monitoring blood glucose levels, regulating electrolyte balance, and controlling skeletal muscle movement are associated with other systems and areas of the brain. For example, blood glucose levels are primarily regulated by the pancreas and related hormonal controls, electrolyte balance is influenced by kidney function and hormonal regulation, and skeletal muscle movement is primarily coordinated by the motor areas of the cerebral cortex in conjunction with the cerebellum and other structures.