Epithelial tissues that consist of a single layer of cells are known as simple epithelium. This type of tissue is characterized by a single layer of cells that are closely packed together, providing a barrier and facilitating processes like absorption, secretion, and filtration.
Simple epithelium can be further categorized into different types based on the shape of the cells, including simple squamous, simple cuboidal, and simple columnar epithelium. Each type serves specific functions in various organs and systems within the body. For instance, simple squamous epithelium is found in areas like the alveoli in the lungs, where rapid exchange of gases occurs, while simple cuboidal epithelium is often found in kidney tubules, playing a key role in secretion and absorption.