Which structure primarily controls heart rate and breathing functions?

• A. Pons varoli
• B. Midbrain
• C. Medulla oblongata
• D. Cerebellum

Answer: (C)

The medulla oblongata houses the primary autonomic centers that regulate vital life-sustaining functions, including heart rate and breathing. It contains the cardiac center, which adjusts heart rate and the strength of contraction, and the respiratory centers that generate and modulate the basic breathing rhythm. These centers integrate signals from sensors in the body (like chemoreceptors for CO2 and O2, and baroreceptors for blood pressure) and from higher brain regions to keep heart and lungs operating in harmony.

The pons helps fine-tune breathing patterns but does not set the basic rhythm. The midbrain is involved in other functions such as vision and alertness, not autonomic control of heart rate and breathing. The cerebellum coordinates movement and balance, not autonomic vital functions.