There are four known forces that are involved in evolution:

1)mutation,

2) genetic drift

3) gene flow or migration

4) selection.

TLS Online TPP Program

#Id: 10109

#XL - T Zoology

Tight junctions prevent the diffusion of: 

Macromolecules

Small water-soluble molecules

Ions

Membrane proteins 

Glycolipids

TLS Online TPP Program

#Id: 10110

#XL - T Zoology

Ca2+-dependent cadherin- mediated adhesion also plays an important role in tight-junction formation, stability, and function

TLS Online TPP Program

#Id: 10111

#XL - T Zoology

Gap junctions permit the passage of molecules as large as 1.2 nm in diameter (molecules smaller than 1200 Da).

TLS Online TPP Program

#Id: 10112

#XL - T Zoology

Ions, low-MW precursors of cellular macromolecules, products of intermediary metabolism, & small intracellular signaling molecules can pass from cell to cell through gap junctions.

TLS Online TPP Program

#Id: 10113

#XL - T Zoology

TLS Online TPP Program

#Id: 10334

#XL - Q Biochemistry

B cell is type of lymphocyte.

B cell synthesized and maturation in bone marrow.