Question

What are the functions of the basement membrane which is found between epithelium and connective tissue?

Answer 1

The basement membrane may be a thin, pliable sheet-like sort of extracellular matrix that gives cell and tissue support and acts as a platform for complex signaling. The basement membrane sits between epithelial tissues including mesothelium and endothelium, and therefore the underlying animal tissue.

Complete answer:
As seen with the microscope, the basement membrane consists of two layers, the basal lamina and therefore the reticular lamina. The underlying animal tissue attaches to the basal lamina with collagen VII anchoring fibrils and fibrillin microfibrils.
The basement membrane acts as a mechanical barrier, preventing malignant cells from invading the deeper tissues. Early stages of malignancy that are thus limited to the epithelial layer by the basement membrane are called carcinoma in place. The basement membrane is additionally essential for angiogenesis (development of latest blood vessels). Basement membrane proteins are found to accelerate differentiation of endothelial cells.
The most notable samples of basement membranes are that the glomerular basement membrane of the kidney, by the fusion of the basal lamina from the endothelium of glomerular capillaries and therefore the podocyte basal lamina, and between lung alveoli and pulmonary capillaries, by the fusion of the basal lamina of the lung alveoli and of the basal lamina of the lung capillaries, which is where oxygen diffusion happens (gas exchange). As of 2017 many other roles for basement membranes are found that include blood filtration and muscle homeostasis.

note:
The primary function of the basement membrane is to anchor down the epithelium to its loose animal tissue (the dermis or lamina propria) underneath. This is often achieved by cell-matrix adhesions through substrate adhesion molecules (SAMs).