The functions of Epithelial tissue include Excretion.

Epithelial tissue is widespread throughout the body.

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Goblet cells are simple columnar goblet shaped like epithelial cells that secrete gel-forming mucins, like mucin

Tubular glands are responsible for the production of ovalbumin, lysozyme, and conalbumin under the simulator control of estrogen, while goblet cells synthesize avidin following exposure to progesterone and estrogen (Tuohimaa et al., 1989).

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microvilli:- The outer surface of columnar epithelial cells lining the intestine of man is brush-bordered.

 The epithelium is a stratified tissue in which the cells all have a fairly round shape when the organ it lines is not distended (stretched out). 

Squamous epithelium is a single layer of flat cells in contact with the basal lamina (one of the two layers of the basement membrane) of the epithelium Cuboidal epithelium is a type of epithelium that consists of a single layer of cuboidal (cube-like) cells.  Ciliated epithelium performs the function of moving particles or fluid over the epithelial surface in such structures as the trachea, bronchial tubes, and nasal cavities. Columnar epithelia are tissues made of a single layer of long epithelial cells that are often seen in regions where absorption and secretion are important features. The cells of this epithelium are arranged in a neat row with the nuclei at the same level, near the basal end.

The large air passages that lead from the trachea (windpipe) to the lungs.