Drawings of compound tubulo-alveolar glands -- showing the branching of their duct system -- and a few secretory end-pieces (alveoli). Ducts and alveoli are lined with epithelium.

• 复管泡状腺模式图--图示分支管道系统--和几个分泌部(腺泡)。导管和腺泡均衬以上皮。