Kaplan Nursing Entrance Practice Exam

Which part of the brain is primarily responsible for controlling the rate of breathing?

1. Cerebral cortex

2. Brainstem

3. Cerebellum

4. Thalamus

The correct answer is: Brainstem

The brainstem is primarily responsible for controlling the rate of breathing. It contains vital centers that regulate automatic functions, including the respiratory rate. Specifically, the medulla oblongata and pons, which are parts of the brainstem, play critical roles in the involuntary control of respiration. The medulla oblongata sets the basic rhythm of breathing, while the pons helps regulate the transition between inhalation and exhalation. This is significant because the respiratory centers in the brainstem respond to various physiological signals, such as carbon dioxide levels in the blood, to adjust the breathing rate accordingly. This automatic control is essential for maintaining homeostasis and ensuring that the body receives adequate oxygen while removing carbon dioxide effectively. In contrast, the cerebral cortex can influence breathing patterns through voluntary control, such as during speaking or singing, but it is not the primary regulatory center for the basic rate of breathing. The cerebellum primarily coordinates motor control and balance and does not significantly contribute to the regulation of respiration. The thalamus serves as a relay station for sensory information but is not involved in the direct control of breathing.