What are hormones?

Hormones are best defined as chemical messengers that regulate physiological processes throughout the body. They are produced by various glands and released into the bloodstream, where they travel to target organs or tissues to elicit specific responses or regulate various functions, such as metabolism, growth, mood, and reproduction.

Understanding this concept is crucial because hormones play a vital role in maintaining homeostasis and coordinating complex physiological activities. They can influence numerous body functions in a precisely controlled manner, ensuring that systems such as the endocrine, nervous, and immune systems work harmoniously.

Other definitions presented in the answer choices misrepresent the function of hormones. For example, while hormones may influence brain activity, they are not limited to that function, and their role encompasses much broader physiological regulation. Similarly, hormones are distinct from proteins involved in chemical reactions, which are typically enzymes, and they are certainly not cellular structures tasked with energy provision. This distinction emphasizes the unique and vital role that hormones play in the body’s regulatory systems.