Give an account of glandular epithelium.

Explanation

Glandular epithelum: Some of the columnar or cuboidal cells the get specialised for the productions of certain secretions, form glandular epitheliumn. The glands are of two types.
Unicellular glands : Consisting of isolated glandular cells such as goblet cells of the gut.
Multicellular glands : Consisting of clusters of cells such as salivary glands. On the basis of the mode of pouring of their secretions, glands are divided into two types namely exocrine and endocrine glands.
Exocrine glands : These glands provided with ducts secrete mucus, saliva, earwax, oil, milk, digestive enzymes etc.
Endocrine glands : These glands are the ductless and their products are hormones, which are carried to the target organs by blood.
Based on the mode of secretion, Exocrine glands are further divided into three types.
1) Merocrine glands : Which release the secretory granules with out the lost of other cellular material. Ex : Pancreas.
2) Apocrineglands : The apical part of the cell is pinched off along with the secretory product. . Ex : Mammary glands.
3) Holocrine glands : The entire cell disintegrates to discharge the contents.
Ex : Sebaceous gland.