Answer:
Lipids are arranged in the form of a bilayer, while proteins are arranged in an irregular and asymmetric way between them. These components confer a certain degree of mobility to the membrane, giving rise to the pattern known as fluid mosaic. Membrane proteins, as will be seen later, can be peripheral or partially or totally integrated into the membrane, being generally globular or fibrous. Its activity is essential for the maintenance of transmembrane gradients and the study of its structure is a priority.
Step-by-step explanation:
The lipid bilayer is a fluid and dynamic structure. This dynamism of the bilayer is known as the fluid mosaic model, in which all the molecules that are part of the bilayer are actively involved, whether they are phospholipids, glycolipids, sterols and proteins, among others. Membrane proteins are located according to the structure of their amino acids, specifically their hydrophilic or hydrophobic properties. They are the main communication tools between the inside and outside of the cell, thanks to them the exchange of molecules such as nutrients or waste products, as well as receiving external signals. Peripheral proteins are attached to the membrane by van der Waals forces, hydrogen or ionic bonds. Generally, they have a net positive charge, the presence of negatively charged lipids in the membrane being necessary to give rise to an electrostatic-type anchoring. Integral (intrinsic) proteins are bound to the lipid bilayer in a very tight way, through covalent bonds and are subdivided into three categories: One- or multi-step transmembrane protein (in alpha helix). They are glycosylated at the extracellular end. They are generally receivers. Protein bound to one or more fatty acids (in the inner sheet). An example of this category is protein G. Protein bound to a lipid of the bilayer (phosphatidyl-inositol) by means of an oligosaccharide (in the outer sheet). As an example we have the neuronal adhesion molecules.