The endocrine system comprises glands that produce hormones, which are vital chemical messengers regulating various bodily functions such as growth, metabolism, and mood. Major glands include the pituitary, thyroid, adrenal glands, ovaries, and testes, each secreting specific hormones essential for health and homeostasis. Hormonal imbalances, whether from overproduction or underproduction, can lead to significant health issues and can be managed through medical interventions.