Explain how the fluid mosaic model accounts for the observed properties of cellular membranes

 The mosaic nature is due to the numerous proteins that are entrenched in the phospholipids bilayer, fluctuate in shape, size and patterns in the same way as the stones or tiles of a mosaic. 

the flexibility is due to individual phospholipids molecules which can move virtual to one another and gives the membrane a flexible structure that is constantly changing shape

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