Simple squamous epithelium:
• It is composed of one layer of flat cells (having one flat nucleus).
• It is found in the alveoli of the lungs, in the kidney glomeruli, in the lining of the heart, blood vessels and lymphatic vessels and in the lining of the ventral body cavities.
• Because this epithelium is the thinnest of all, it is well adapted for diffusion (for example gas exchange between alveoli and blood in the lung or exchange of waste and nutrients between blood and surrounding tissues), filtration (of plasma in the kidney glomeruli to produce urine), secretion (of a lubricating substance in the lining of the body cavities).