)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