Answer:
Endocrine glands secrete hormones over a membrane into the bloodstream.
Explanation:
The endocrine glands are characterized by the secretion of hormones that pass directly into the bloodstream. This is because, unlike the exocrine glands, they do not have ducts.
Hormones leave the endocrine cell through transmembrane transport, to reach the blood capillaries and from there to the general circulation.Once the hormones are released into the bloodstream they bind to specific effector cells, attaching to membrane receptors for these substances.