Hormones are chemical messengers produced by glands in the endocrine system that regulate various physiological processes in organisms. They play critical roles in the growth, development, metabolism, and reproduction of living beings. For instance, growth hormones stimulate cell division and elongation, promoting overall growth, while other hormones like insulin regulate glucose metabolism. The balance of these hormones is essential for maintaining homeostasis, and any disruption can lead to growth disorders or metabolic diseases.