Glandular Epithelium

The cells of glandular epithelium are specialized to secrete substances. They are organized into structures called glands. Endocrine glands secrete directly into the bloodstream. Exocrine glands secrete through tube-like ducts out onto epithelial surfaces. Exocrine glands can be divided into simple glands, which secrete through a single, unbranched duct; and compound glands, which secrete through a more complex, branched duct system.