What is the primary function of a hormone?

The primary function of a hormone is to act as a chemical messenger produced by the endocrine glands. Hormones are released into the bloodstream and travel to various tissues and organs, where they exert their effects by binding to specific receptors. This communication system regulates numerous bodily functions, including growth, metabolism, mood, and reproductive processes.

Hormones coordinate complex processes by initiating or inhibiting a variety of physiological activities. For instance, insulin regulates blood sugar levels, while adrenaline affects the body’s response to stress. Their role in facilitating communication between different parts of the body highlights the importance of hormones in maintaining homeostasis and overall health.

The other choices do not accurately describe the function of hormones. Neurotransmitters, for example, are chemical messengers too, but they primarily operate within the nervous system, transmitting signals between neurons. Substance that blocks neurotransmitter effects refers to antagonists rather than hormones. Lastly, while some hormones are derived from amino acids, describing them as merely a type of amino acid does not capture their functional role as signaling molecules in the body.