The endocrine system regulates the body by means of what?

The endocrine system regulates the body primarily through hormones. Hormones are chemical messengers produced by various glands in the endocrine system, such as the pituitary gland, thyroid gland, adrenal glands, and others. These hormones are secreted directly into the bloodstream, allowing them to travel to target organs and tissues, where they exert their effects on various bodily functions. This regulation involves processes such as growth, metabolism, reproduction, and response to stress.

Unlike neurons, which communicate through electrical signals and synapses in the nervous system, the endocrine system operates via a more gradual and sustained signaling process. Autoimmune responses involve the immune system attacking the body's own tissues and are not a mechanism of bodily regulation in the same way. Enzymes, while important for facilitating biochemical reactions, do not function as regulatory agents in the systemic and wide-ranging manner that hormones do. Therefore, hormones are the key agents through which the endocrine system exerts its regulatory effects.