Final answer:
Squamous cells are flat shaped cells that form part of epithelial tissue, functioning in protection and diffusion depending on their arrangement, which can be a simple layer for diffusion or stratified layers for protection.
Step-by-step explanation:
Squamous cells are part of epithelial tissue and are flat shaped. These cells are distinguished by their thin, flat appearance and are typically involved in protective or absorptive functions, depending on where they are found in the body. For instance, when squamous epithelial cells are arranged in a single layer, known as simple epithelium, they facilitate processes like diffusion, which is essential in areas of gas exchange in the lungs and in the exchange of nutrients and waste at blood capillaries.
Stratified squamous epithelium tissue consists of multiple layers of cells with the most apical layer being flat, scale-like cells. This arrangement is particularly vital for providing protection from abrasion and damage, as can be observed in the skin and tissues lining the mouth and vagina.