Answer:
midbrain, medulla, and pons
Explanation:
The brainstem (also known as truncus encephali) is localized in the posterior part of the brain, in the base between cerebral hemispheres and the cervical cord. <em>It's divided into three parts, the midbrain or mesencephalon, the pons or mesencephalon, and the medulla oblongata also known as long medulla or myelencephalon.</em> <em>In the image I added you can see the brainstem structure.</em>
Some of the brainstem functions include the regulation of respiratory and cardiac function, thermoregulation, and other functions related to vision, sleep, etc.
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