Sources of hormones in humans = the endocrine system [Fig. 37.2] 3. Target cells = cells with receptors for a given chemical messenger that can alter their activities in response to messenger.- Hormones are transported throughout the body by the blood, but they only elicit responses in target cells.. Do not diffuse into cells. b. Target cells have specific receptor for hormone on cell surface. c. Hormone binds to receptor and causes a second messenger to be released within the cell.
Definition of herder. : one that herds; specifically : a person who manages, breeds, or tends to livestock : herdsman 1.
A cowboy is an animal herder who tends cattle on ranches in North America, traditionally on horseback, and often performs a multitude of other ranch-related tasks.he Florida cowhunter or  cracker cowboy of the 19th and early 20th centuries was distinct from the Texas and California traditions. Florida cowboys did not use lassos to herd or capture cattle. Their primary tools were bullwhips and dogs.