Final answer:
A sheet of closely joined epithelial cells rests on a basement membrane, which includes the basal lamina and the reticular lamina, and supports the epithelial layer above the connective tissue, also known as the lamina propria.
Step-by-step explanation:
A sheet of closely joined epithelial cells rests on a basement membrane which comprises the basal lamina and the underlying reticular lamina.
The basal lamina, a layer of extracellular material, primarily consisting of glycoproteins and collagen, acts as an anchor for the epithelial layer, providing support and maintaining its structure.
The basement membrane plays a critical role in supporting and separating the epithelial cells from the underlying connective tissue. This connective tissue is known as the lamina propria, which helps support the epithelial layer.
Epithelial tissues serve as coverings or linings of body surfaces and cavities, as well as forming the glandular tissues.
They are designed for protection, absorption, transport, and secretion, with each cell displaying polarity—specific differences in structure and function between their apical and basal surfaces.
Furthermore, epithelia are highly cellular, with very little extracellular space, and adjoining cells are often bound by cell junctions.
For example, the skin represents a specific type of epithelial tissue called stratified squamous epithelium, where multiple layers of cells provide protection against external abrasion and damage.
The skin, also referred to as the cutaneous membrane, exhibits this cell arrangement for enhanced protective functions.