Lamellar Model of Plasma Membrane

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A) Danielli - Davson Model / Sandwich Model / P-L-P Model:

This model of plasma membrane was proposed by Danielli and Davson in the year 1935. According to this the plasma membrane is trilaminar, where lipids bilayer is sandwitched between the two protein layers. Hence it is also called as P-L-P model (P=protein, L=lipid).
This model fails to explain functional specificity and active transport through membranes.


B) Unit Membrane Model / Robertson Model:

This model of plasma membrane was proposed by Robertson in the year 1959. According to Robertson, all membranes have the same basic structure but they have their own distinctive composition. Example: Internal organelles have more proteins than lipids in eukaryotic cells whereas plants and bacteria have more lipids than proteins. This model fails to explain the membranes stability and permeability.

Related Articles:
1) Biomembranes
https://anaszoology.blogspot.com/2022/08/biomembranes.html







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