Which part of the brain is the “master gland” and plays a major role in maintaining homeostasis?
A hypothalamus
B thalamus
C corpus collasum
D basal ganglia
E ventricles
E cerebrum
G brainstem
The Correct Answer and Explanation is:
Correct Answer: A. hypothalamus
The hypothalamus is considered the “master gland” of the brain because it plays a central role in regulating many bodily functions essential to homeostasis. Although the title “master gland” is often attributed to the pituitary gland, it is the hypothalamus that controls the pituitary and, therefore, has the ultimate regulatory authority.
The hypothalamus is a small but vital structure located below the thalamus and above the brainstem. Its main function is to link the nervous system to the endocrine system via the pituitary gland. It helps regulate a wide variety of critical bodily functions including temperature, hunger, thirst, sleep, circadian rhythms, and emotional activity. It also controls the autonomic nervous system, which governs involuntary functions such as heart rate and digestion.
One of the most important roles of the hypothalamus is hormone regulation. It produces releasing and inhibiting hormones that instruct the anterior pituitary gland on when to release its hormones into the bloodstream. For instance, when the body is under stress, the hypothalamus signals the pituitary to release adrenocorticotropic hormone (ACTH), which then stimulates the adrenal glands to produce cortisol.
Moreover, the hypothalamus plays a role in maintaining water balance by releasing antidiuretic hormone (ADH) and influences reproductive behaviors by regulating hormones like oxytocin. It also adjusts the body’s thermostat and signals behaviors like shivering or sweating to maintain internal temperature.
Other brain parts mentioned in the options have different primary functions. The thalamus relays sensory signals, the corpus callosum connects the two hemispheres, the basal ganglia control movement, the ventricles store cerebrospinal fluid, the cerebrum handles higher cognitive functions, and the brainstem manages basic life functions. Only the hypothalamus integrates both nervous and endocrine signals to sustain homeostasis.
