)٢ ( Glandular epithelium• It is a modified type of
epithelial tissue specialized in
• production of secretions.• It is classified :1- According to the duct.2- According to the
secretory part.3- According to nature of
secretion.4- According to mode of
secretion.
According to the duct-I* Exocrine glands: possess ducts e.g. salivary glands
According to the duct-I* Endocrine glands: have no ducts and the secretion
pass directly to the blood e.g.Thyroid G.
Pituitary G.Adrenal G.
According to the duct-I• * Mixed glands: have the two types e.g.
Pancreas
(B) Branching of the duct:* Simple glands possess one unbranched duct
e.g. intestinal, gastric glands
(B) Branching of the duct:• Compound glands
have branched duct system
• e.g. salivary glands.
According to the secretory part.-II(A) Number of cells :• Unicellular glands: formed of a single cell• e.g. goblet cells.
According to the secretory part.-II(A) Number of cells :• Multicellular glands:formed of numerous cellse.g. salivary glands,
pancreas
liver
According to the secretory part.-IIShape of the secretory part :• * Tubular glands: have
tubular secretory parts e.g. intestinal glands and liver
• * Alveolar glands: have alveolar (flask shaped) or acinar (grape like) secretory parts e.g. sebaceous and mammary glands.
• * Tubulo-alveolar glands: the secretory part is formed of the two types e.g. salivary glands and pancreas.
Branching of the secretory part:• * Simple glands: have
unbranched secretory parts e.g. intestinal glands.
• * Branched glands:have branched secretory parts e.g. salivary glands,
• liver and • pancreas.
According to nature secretion-III• * Mucous glands: produce viscid mucous poor in
enzymes e.g. goblet cells and minor salivary glands.• * Serous glands: produce watery solution rich in
enzymes e.g. Parotid glands and pancreas.• * Mucoserous glands: produce both types of
secretions e.g. submanibular and sublingual glands.• Sweat glands of skin produce watery secretion
containing some enzymes and waste products • Oily glands: secrete fatty secretion e.g. sebaceous
and tarsal glands• Waxy glands: secret waxy secretion e.g. ceruminous
glands of the external canal.• Cellular glands: produce cells e.g testis and ovary
According to method (mode) of secretion:-VIMerocrine glands : the secretory cells are not
destroyed during secretion e.g. salivary glands.
According to method (mode) of secretion:-VIApocrine glands : the apical part of the cells is
destroyed during secretion e.g. mammary glands.
According to method (mode) of secretion:-VIHolocrine glands: the whole cell is destroyed during secretion e.g. sebaceous glands.
(3) NEUROEPITHELIUM• Definition: • A modified type of epithelial tissue
specialized for receiving of sensory stimuli.
(3) NEUROEPITHELIUM
• SITES:Taste budsOlfactory epith.Organ of CortiCrista ampularisMacula sacculi,utriculi