Figure 427

Mucus surface cells of stomach. Photomicrograph of stomach surface. The epithelial cells lining the surface are all mucus-secreting cells, as are the cells lining the gastric pits (P). The cells of the gastric pit form simple tubular glands. x260.

table 4.3. Classification of Multicellular Glands

Classification

Typical location

Features

Simple tubular

Simple coiled tubular

Simple branched tubular

Large intestine: intestinal glands of the colon

Secretory portion of the gland is a straight tube formed by the secretory cells (goblet cells)

Skin: eccrine sweat gland

Coiled tubular structure is composed of the secretory portion located deep in the dermis

Stomach: mucus-secreting glands of the pylorus

Branched tubular glands with wide secretory portions are formed by the secretory cells and produce a viscous mucous secretion

Simple

Urethra: paraurethral and periurethral glands

Simple acinar glands develop as an outpouching of the transitional epithelium and are formed by a single layer of secretory cells

Branched acinar

Stomach: mucus-secreting glands of cardia

Branched acinar glands with secretory portions are formed by mucus-secreting cells; the short, single-duct portion opens directly into the lumen

Compound tubular

Duodenum: submucosal glands of Brunner

Compound tubular glands with coiled secretory portions are located deep in the submu-cosa of the duodenum

Compound acinar

Compound tubuloacinar

Pancreas: excretory portion

Submandibular salivary gland

Compound acinar glands with alveolar-shaped secretory units are formed by pyramid-shaped serous-secreting cells

Compound tubuloacinar glands can have both mucous branched tubular and serous branched acinar secretory units; they have serous end-caps (demilunes)

Mucous and serous glands are so named because of the type of secretion produced

0 0

Post a comment