Extracellular matrix or glucocalyx
A large part of the cells of multicellular beings are covered by the extracellular matrix, composed of macromolecules secreted by the cell. It's formed by:
- Fibrous proteins.
- Structural glycoproteins. They form a network of elements that interact with the other components of the extracellular matrix and with those of the cell surface. Among them we can highlight.
- Fibronectin. It collaborates in cell adhesion, appearing as long and insoluble fibrils.
- Laminin. It is the first protein that allows cell adhesion during embryonic development.