The basis of the plasmalemma is a layer of lipids, which has two rows of molecules. The dynamic properties of the membrane are due to the mobility of its molecular organization. Proteins and lipids are interconnected in the membrane intermittently and form a mobile, flexible, temporarily connected into a single whole structure, capable of structural changes. In this case, for example, the relative position of the membrane components is easily changed. Due to this, membranes can change their configuration, i.e., have fluidity. This provides the possibility of phage and pinocytosis.
Lipids are insoluble in water; therefore, they create a barrier in the cell that impedes the movement of water and water-soluble substances from one compartment to another.
Protein molecules, however, make the membrane permeable to various substances through specialized structures called pores.
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