Explain why the plasma membrane can be described as having a fluid mosaic structure.

2 years ago


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Danial Kunze

10 Answers

Aqeel A Profile Picture
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Fluid - The lipid bilayer is viscous and individual phospholipids can move position.

Mosiac - Lipid bilayer is embedded with several proteins like tiles in a mosiac.

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Sara B

Hi Daniel!

The cell membrane is described as a fluid mosaic model due to it's structure.

The fluid part refers to the phospholipid bilayer (the hydrophilic heads on the outside and the hydrophobic tails on the inside) which provides elasticity to the cell membrane structure

The mosaic part refers to the different components of the cell membrane such as the phospholipids, proteins etc within the cell membrane

Hope this helps!

Peter G Profile Picture
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It is fluid because it is flexible due to different quantities of cholesterol within the membrane. The mosaic structure refers to the varied composition of the molecules that includes phospholipids as well an array of different structural and functional proteins, carbohydrates and lipids.

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Hi Danial! The plasma membrane is described as having fluid structure because the individual phospholipid molecules making up the bilayer can move around making the membrane structure flexible and constantly changing in shape. Mosaic because the embedded proteins in the bilayer resemble tiles of a mosaic due to their varying shapes, sizes and pattern.

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Cadence Ooi

Plasma membrane has a fluid mosaic structure as it is flexible due to presence of cholesterol within the membrane. The 'Mosaic' term comes from the proteins and cholesterol that are randomly inserted into the membrane and thus it looks like a mosaic. The 'fluid' term is a result of the ability for the molecules making up the plasma membrane to move around each other freely.

Claire Morley

The plasma membrane is fluid in the sense that all the components within the phospholipid bilayer can move around each other, they are not in a fixed position. For example, a protein channel can move from one side of the cell to another.

The mosaic part is from how it appears to look like mosaic art because there are so many components integrated and mixed amongst the phospholipids.

Monisha Corotana

The fluid mosaic model of the plasma cell membrane is how scientists describe what cell membranes look like and how they function. The plasma membrane is formed of a variety of different molecules- hence it has a mosaic-like structure. Additionally, the molecules are able to move around and change much like the sea- hence it is fluid. The fluid mosaic structure allows for cell membrane permeability and the control of substances in and out of the cell.


It's described as mosaic due to the proteins and cholesterol that is embedded in the phospholipid bilayer giving it this 'mosaic' appearance. The fluidity term arises as some parts of the membrane are able to move around freely. There are three key factors that affect the membranes fluidity 1) temperature 2) cholesterol content 3) whether the fatty acid chains are saturated or unsaturated


The plasma membrane has cholesterol in it that changes rigidity depending on temp this means that the membrane can go from being more fluid or more rigid . The mosaic portion of the name comes from the different sized Glycoproteins in the membrane that resemble a mosaic

NIDA Farsana

The fluid mosaic model describes the cell membrane as a tapestry of several types of molecules that are constantly moving.This movement helps the cell membrane maintain its role as a barrier between the inside and outside of the cell environments.

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