These cells form of the Simple epithelial tissue:

(i) Squamous epithelium. The cells of this tissue are broad, flat forming a pavement like appearance. It is found in the alveoli of the lungs. Bowman’s capsule, membranous labyrinth of internal ear, peritoneum of coelom and blood vessels.

(ii) Cuboidal epithelium. The cells of this tissue are cube like in appearance. It is found in kidney tubules and salivery glands etc.

(iii) Columnar epithelium. The cells of this tissue are more tall than wide, placed side by side. Their nuclei are situated near the bases. They may have on their free surfaces finger like projections—the microvilli. This tissue usually lines the internal surfaces of stomach and intestine.

(iv) Ciliated epithelium. The cells of this tissue are modifications of columnar epithelial cells. They have on their free ends many small, vibratile cilia. These are found in kidney tubules, trachea oviduct etc.

(v) Striated squamous epithelium. Cells of this tissue are squamous epithelial cells which are arranged in many layers to prevent wear and tear of parts. Tounge, oesophagus and lining of mouth are also made of striated squamous epithelium.

(vi) Glandular epithelium. Sometimes the cells aggregate to form masses of cells, the glands. These glands secrete juices helpful to the organism. We have a number of such glands in our body, viz. sweat glands which secrete sweat; oil glands which secrete oily substance. Both these glands are present in the skin. Salivery glands present in the mouth secrete saliva.

(vii) Sensory epithelium. At certain places the cells of columnar epithelium gets modified into sensory cells. These cells are innervated at their bases by sensory nerve fibres. Such cells are found in sense organs.

(viii) Germinal epithelium. They are found in gonads i.e., testes and ovaries. They produces gametes i.e., sperms and ova.