In Meristematic zone, 

cells divide both in the direction of the root base to form cells that will differentiate into the tissues of the functional root and in the direction of the root apex to form the root cap

TLS Online TPP Program

#Id: 10059

#XL - T Zoology

Heterophilic Binding

A CAM on one cell can directly bind to a different class of CAM on an adjacent cell

TLS Online TPP Program

#Id: 10060

#XL - T Zoology

The formation of many cell-cell adhesions entails two types of molecular interactions:

1.Trans binding interactions 

2. Cis binding interactions

TLS Online TPP Program

#Id: 10061

#XL - T Zoology

Trans interactions (intercellular or adhesive interactions)

CAMs on one cell bind to CAMs on an adjacent cell. 

TLS Online TPP Program

#Id: 10062

#XL - T Zoology

In cis interactions (intracellular or lateral interactions)

monomeric CAMs on one cell bind to one or more CAMs in the same cell’s plasma membrane

TLS Online TPP Program

#Id: 10063

#XL - T Zoology

CAMs fall into one of four major families: 

Cadherins

Immunoglobulin (Ig) superfamily

Integrins

Selectins

TLS Online TPP Program

#Id: 10064

#XL - T Zoology

The adhesiveness of cadherins depends on the presence of extracellular Ca2+