Question

What is basement membrane?

Answer 1

The basement membrane is a thin, fibrous, extracellular matrix of tissue that separates the lining of an internal or external body surface from underlying connective tissue in metazoans. This surface may be epithelium (skin, respiratory tract, gastrointestinal tract, etc.), mesothelium (pleural cavity, peritoneal cavity, pericardial cavity, etc.) and endothelium (blood vessels, lymph vessels, etc.). The basement membrane is composed of two layers, the basal lamina and the underlying layer of reticular connective tissue. The underlying connective tissue attaches to the basal lamina with collagen anchoring fibrils and fibrillin microfibrils. The two layers together are collectively referred to as the basement membrane.