What is the role of the pineal gland?

The pineal gland's primary function is to produce melatonin, which plays a crucial role in regulating sleep-wake cycles. Melatonin secretion is influenced by light exposure; it typically increases in darkness and decreases with light. This hormone helps to signal the body when it is time to sleep, effectively managing circadian rhythms.

While other glands and hormones manage functions such as metabolism, growth, and calcium regulation, these activities are not the focus of the pineal gland. Its specific role in melatonin production is vital for maintaining a healthy sleep pattern and ensuring that the body aligns its biological processes with the day-night cycle.