Infidelity always has a purpose to it, although most often that purpose is not known or understood, and must be, in order to really answer the questions around Once a cheater, always a cheater. All behavior is purposeful and people don't do anything without a reason for doing it.nfidelity always has a purpose to it, although most often that purpose is not known or understood, and must be, in order to really answer the questions around Once a cheater, always a cheater. All behavior is purposeful and people don't do anything without a reason for doing it.
In other words, the extracellular matrix largely determines how a tissue looks and functions. The extracellular matrix is made up of proteoglycans, water, minerals, and fibrous proteins. A proteoglycan is composed of a protein core surrounded by long chains of starch-like molecules called glycosaminoglycans.
The Extracellular Matrix (ECM). While it is true that all living things are made of cells, that is only part of the story. Most of the cells in multicellular organisms are surrounded by a complex mixture of nonliving material that makes up the extracellular matrix (ECM).In some cases, the ECM accounts for more of the organism's bulk than its cells.1  In plants, the ECM is primarily composed of cellulose. [ Link to a discussion. In vertebrates, the ECM is made of a complex mixture of carbohydrates and proteins (plus minerals in the case of bone). 2  It is the ECM of vertebrates that will be discussed on this page.