Epithelial tissue is a type of tissue that covers the surface of the body and lines various organs and cavities. It has several functions that include protection, secretion, and absorption. However, it does not perform the function of conduction.

Protection
Epithelial tissue serves as a protective barrier against physical, chemical, and biological damage. It protects the underlying tissues and organs from injury, abrasion, and invasion by microorganisms.

Secretion
Epithelial tissue also secretes various substances such as mucus, enzymes, and hormones. For example, the epithelial cells in the stomach secrete hydrochloric acid and digestive enzymes that aid in the digestion of food.

Absorption
Epithelial tissue is involved in the absorption of nutrients, water, and other substances from the external environment. For example, the epithelial cells in the small intestine absorb nutrients from digested food and transport them to the bloodstream.

Conduction
Epithelial tissue does not perform the function of conduction. Conduction refers to the transmission of nerve impulses from one nerve cell to another. This function is performed by nervous tissue, which is a separate type of tissue.

In conclusion, epithelial tissue performs several important functions such as protection, secretion, and absorption, but it does not perform the function of conduction.