Conceptually the situation is analogous to radio broadcasting, in which a message is radiated in all directions but can only be picked up by specially tuned receivers.  Or another way to look at the system is that todays patients may understand the idea that the endocrine hormones are the softwear and the endocrine organs are the hardwear element.

Many misconceptions with endocrine disorders, ask the husbands/wives, children or parents of the endocrines about the influence on family dynamics. One has no idea what it feels like to have an endocrine disorder until they actually have one.

— Janet Elwick

Cells that Secrete Hormones

Some organs and tissues are not classed as endocrine glands but contain cells that contain hormones. These include the hypothalamus, thymus, pancreas, ovaries, testes, kidneys, stomach, liver, small intestine, skin, heart, adipose tissue and placenta.