What is a single layer of flat cells?

A single layer of flat cells is referred to as simple squamous epithelium. This type of tissue consists of a single layer of cells that are wider than they are tall, creating a thin, flat appearance. Simple squamous epithelium is commonly found in areas where diffusion or filtration occurs, such as the lining of blood vessels (endothelium) and the alveoli in the lungs. Its structure allows for efficient exchange of gases and nutrients.