A gland is an organ in an animal's body that synthesizes a substance for release such as hormones or breast milk, often into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland).
Glands can be divided into two groups:
The type of secretory product of an Exocrine gland may also be one of three categories:
As growth proceeds, the column of cells may divide or give off offshoots, in which case a compound gland is formed. In many glands the number of branches is limited, in others (salivary, pancreas) a very large structure is finally formed by repeated growth and sub-division. As a rule, the branches do not unite with one another, but in one instance, the liver, this does occur when a reticulated compound gland is produced. In compound glands the more typical or secretory epithelium is found forming the terminal portion of each branch, and the uniting portions form ducts and are lined with a less modified type of epithelial cell.
Glands are classified according to their shape.
A list of human endocrine glands is available here.
Ultrastructure of the surface structures and secretory glands of the rosette attachment organ of Gyrocotyle urna (Cestoda: Gyrocotylidea)
Sep 01, 2008; Key words: Cestoda, Gyrocotylidea, Gyrocotyle urna, rosette organ, adhesive secretion, secretory glands, ultrastructure Abstract....
Ultrastructure of the apical glandular region of the scolex of Proteocephalus torulosus (Cestoda: Proteocephalidae)
Oct 01, 2004; Key words: Cestoda, Proteocephalus torulosus, apical glandular region, transmission electron microscopy Abstract. In the apical...