The hair cells are arranged in four rows: 

Three rows of outer hair cells (20,000)

One row of inner hair cells (3500)

TLS Online TPP Program

#Id: 1421

#Unit 4. Cell Communication and Cell Signaling

Integrins bind extracellular matrix (ECM) glycoproteins, 1. Laminins  

2. Collagens 

3. Fibronectin

4. Vitronectin

TLS Online TPP Program

#Id: 1422

#Unit 4. Cell Communication and Cell Signaling

Fibronectin binds to integrin through an RGD motif.

TLS Online TPP Program

#Id: 1423

#Unit 4. Cell Communication and Cell Signaling

The binding of integrins to their ligands depends on extracellular divalent cations(Ca+2 & Mg+2).

TLS Online TPP Program

#Id: 1424

#Unit 4. Cell Communication and Cell Signaling

The α subunit of each integrin is the primary determinant of its extracellular ligand specificity.

TLS Online TPP Program

#Id: 1425

#Unit 4. Cell Communication and Cell Signaling

Several integrin α subunits contain, I-domain, which can mediate binding of integrins to various collagens in the ECM.

TLS Online TPP Program

#Id: 1426

#Unit 4. Cell Communication and Cell Signaling

I-domains also recognize CAMs on other cells,  ICAMs, VCAMs and participate in cell-cell adhesion.