What is the difference between the basal lamina and the basement membrane in terms of their structure and function?

The basal lamina is a thin layer of extracellular matrix secreted by epithelial cells, while the basement membrane is a thicker structure that includes the basal lamina along with additional layers produced by connective tissue cells. The basal lamina provides structural support and acts as a barrier, while the basement membrane also serves as a filter and plays a role in cell signaling and tissue organization.