Which part of the brain is primarily responsible for controlling heart rate and hunger?

The hypothalamus is a crucial part of the brain that plays a significant role in regulating various autonomic functions, including heart rate and hunger. It serves as a control center for many involuntary bodily functions necessary for survival, such as temperature regulation, thirst, and the sleep-wake cycle, in addition to hunger signaling and the regulation of metabolic processes.

One of the primary functions of the hypothalamus is its ability to detect changes in the body's internal environment and respond accordingly. For instance, when energy levels are low, the hypothalamus can trigger feelings of hunger to motivate feeding behavior, while also influencing heart rate through its connections with the autonomic nervous system. This interaction helps maintain homeostasis, which is essential for the body's optimal functioning.

In contrast, the cerebellum is primarily involved in motor control and coordination rather than autonomic functions. The cortex, specifically the cerebral cortex, is responsible for higher cognitive functions, sensory perception, and voluntary motor actions. The thalamus acts as a relay station for sensory and motor signals but does not play a direct role in regulating hunger or heart rate. Therefore, the hypothalamus is the correct answer, as it specifically manages these physiological needs and homeostatic processes.