The basement membrane is composed of two layers, the basal lamina and the underlying layer of reticular connective tissue. The clear layer closer to the epithelium is called the lamina lucida, while the dense layer closer to the connective tissue is called the lamina densa.

Basement Membrane Composition

Basement membrane is a thin, specialized extracellular matrix layer that separates epithelial, endothelial, muscle, or nerve cells from the underlying connective tissue. It is primarily composed of extracellular matrix proteins, glycoproteins, and proteoglycans. The correct option for the composition of the basement membrane is:

a) Hyaluronic Acid Glycoproteins

Hyaluronic Acid

Hyaluronic acid is a linear polysaccharide that is widely distributed in the extracellular matrix of various tissues. It has a high molecular weight and is composed of repeating units of D-glucuronic acid and N-acetylglucosamine. Hyaluronic acid is an important component of the basement membrane and helps in maintaining its structural integrity.

Glycoproteins

Glycoproteins are proteins that contain covalently attached oligosaccharide chains. They are important components of the basement membrane and play a crucial role in cell adhesion, migration, and differentiation. The major glycoproteins present in the basement membrane are laminin, fibronectin, and collagen IV.

Other Components

Apart from hyaluronic acid and glycoproteins, the basement membrane also contains other components such as proteoglycans, nidogens, and various growth factors. Proteoglycans are composed of a core protein and one or more glycosaminoglycan chains. They provide structural support to the basement membrane and regulate cell growth and differentiation. Nidogens are glycoproteins that help in the stabilization of the basement membrane by connecting laminin and collagen IV. Growth factors are signaling molecules that regulate various cellular processes such as cell proliferation, differentiation, and migration.

Conclusion

In conclusion, basement membrane is primarily composed of hyaluronic acid, glycoproteins, proteoglycans, nidogens, and growth factors. These components work together to maintain the structural integrity of the basement membrane and regulate various cellular processes.

On under the epithelial tissue basement membrane is found which is made up of hyaluronic acid and glycoprotein..