THE ENDOCRINE SYSTEM Endocrine glands release their secretions directly into the blood. In other words they have no _____________________. Endocrine glands secrete chemicals called ____________________. What are hormones? _________________________________________________________________________ _________________________________________________________________________ Hormones are transported from the endocrine glands to all parts of the body by the ____________________. Although hormones are carried throughout the body they only affect specific ____________ organs and tissues. What are the two classes of hormones and what method do they use to elicit their effects? _________________________________________________________________________ _________________________________________________________________________ Paracrine secretions act ____________ and autocrine secretions act on _____________. A. Itself; locally B. Normally; whim C. Locally; itself What are the three things that can stimulate hormone release? 1. 2. 3. When the number of receptors on a target cell increases this is called ________ ____________. When the number of receptors on a target cell decrease this is called ________ _____________. 1. ___________________ one hormone opposes the action of another 2. ___________________ the combined effects of hormones are amplified 3. ___________________ one hormone requires another one for its full effect