BCT Lab Practical 1 Practice Test

Epithelial tissue is named by how many cell layers there are and by the shape of the cells at the surface that faces the lumen or outside, not by the shape of cells on the basal side. The basal surface sits on the basement membrane and mainly serves for attachment and polarity; it doesn’t determine the name. The visible, apical surface shows cells that are flat (squamous), cube-shaped (cuboidal), or tall and columnar, and this apical shape is what drives the classification alongside the layering. For example, a single layer of flat apical cells is simple squamous, while multiple layers with flat outermost cells are stratified squamous. Transitional epithelium is a special case that can change shape with stretch, but the naming still relates to the surface cell appearance and layering. So naming based on the basal surface is not correct.