Basal lamina

 The basal lemina or the basal membrane is a type of tissue that is not made from cells purely. Most part of it consisted of extracellular spaces which contained various macromolecules constitutiong the extracellular matrix. The main content found in the basal lamina is laminin however it varies from tissue to tissue. They are normally found in bone,tendon and the dermal layer of the skin. The basal lamina a thin but it is extremly tough and flexible. It not only surrounds epithelial cells it also surrounds nonepithelial cells. It's primary function is to separate cells from the surrounding connective tissue. Besides having simple structural function it also has filtering roles in the kidney glomerulus. They are able to determine cell polarity, regulating cell metabolism, protein organization in adjacent plasma membranes, cell survival and etc.

Reference

1. Molecular Biology Of The Cell ( Fifth Edition )