What part of the brain contains the dorsal and ventral groups that control the respiratory system?

The part of the brain that contains the dorsal and ventral groups responsible for controlling the respiratory system is the medulla. The medulla oblongata, which is located in the brainstem, plays a crucial role in regulating vital functions, including respiration.

Within the medulla, the dorsal respiratory group primarily initiates the rhythm of breathing by sending impulses to the diaphragm and other muscles involved in inspiration. In contrast, the ventral respiratory group facilitates both expiration and further enhances the respiratory rhythm during high activity. Together, these groups work to maintain an appropriate rate and depth of breathing in response to the body's needs, such as during exercise or resting states.

The cerebrum, while involved in higher cognitive functions and voluntary movements, does not directly control the autonomic functions of respiration. The cerebellum primarily coordinates motor control but does not play a direct role in regulating breathing. The thalamus acts as a relay station for sensory and motor signals but is not involved in the control of respiratory rhythm. Thus, the medulla is the vital center for respiratory control, making it the correct answer.