Biological Systems MCAT Practice Exam

What is the medulla oblongata's primary function in the autonomic nervous system?

1. Regulating emotional responses

2. Controlling heartbeat and breathing

3. Facilitating voluntary movement

4. Processing sensory information

The correct answer is: Controlling heartbeat and breathing

The medulla oblongata plays a crucial role in maintaining vital autonomic functions, specifically by controlling heartbeat and breathing. It serves as a relaying station between the spinal cord and the brain while managing autonomic functions necessary for survival. Located at the base of the brainstem, the medulla contains centers that directly regulate the cardiovascular and respiratory systems. For example, it adjusts the rate and depth of breathing based on the body’s metabolic needs and monitors blood pressure, heart rate, and other involuntary functions vital for homeostasis. The other options reference different functions that are not primarily associated with the medulla oblongata. While emotional responses are more linked to structures like the amygdala and the limbic system, voluntary movement is controlled by the motor cortex and other areas of the brain involved in coordination. Sensory information processing primarily occurs in regions like the thalamus and the cerebral cortex. Thus, the role of the medulla oblongata is specifically focused on sustaining critical autonomic processes such as heartbeat and breathing, which makes it an integral component of the autonomic nervous system.