Answer:
Hormones.
Step-by-step explanation:
Hormones are substances produced by the glands that make up the so-called endocrine system. Each hormone has a different function, but some work together. From the endocrine glands in which each is produced, hormones are released into the blood and from there reach all the cells in the body - but will only act on those to which they are called, precisely target cells.
The cells have, on their membrane or inside, special receptors for that particular hormone. So we can say that hormones work as messengers that transmit orders with the right addresses and recipients. The central command of the team is the pituitary gland, located in the brain that, in addition to producing their own hormones, stimulates the other endocrines to manufacture the rest. Some have the function of leaving your gland and traveling to another to warn you that you must produce the hormone that will perform the desired task.