Question

The extracellular amorphous ground substance proteoglycans form a porous, hydrated gel that fills the extracellular space and resists crushing forces. This is because the glycosaminoglycan chains of proteoglycans contain sulfate and carboxyl groups that bind large numbers of ________?

1) water molecules
2) proteins
3) lipids
4) ions

Answer 1

The glycosaminoglycan chains of proteoglycans contain sulfate and carboxyl groups that bind large numbers of water molecules, which helps form a hydrated gel that resists crushing in the extracellular matrix.

Step-by-step explanation:

The glycosaminoglycan chains of proteoglycans are key components of the extracellular matrix, which fill the extracellular space with an amorphous ground substance. This ground substance is able to resist crushing forces because it forms a hydrated gel-like matrix.

These glycosaminoglycan chains contain sulfate and carboxyl groups that can bind large numbers of water molecules, which creates the gel's resistance to compression. Proteoglycans consist of a core protein with polysaccharide branches, and these chains can trap and hold water, giving the extracellular matrix its unique properties, which include providing structural stability and facilitating communication among cells.