Specialization Of Cellular Function

All cells in a multicellular organism have the same basic needs for survival and, because they share a common genetic heritage, have the same potential for carrying out all of the various cellular functions. However, the "social contract'' that governs cells in a complex organism requires that different cells selectively develop particular capabilities that allow them to perform or participate in the performance of certain specialized tasks on behalf of the organism as a whole. Red blood cells, for example, have the highly specialized ability to transport oxygen and carbon dioxide, while some cells in the gastric mucosa are specialized to secrete acid, and muscle cells are equipped with the structural and enzymatic apparatus that generates the contractile force that propels the organism toward its next meal or away from predators. Determination of which cellular capacities will be expressed and which will remain dormant resides in the province of the differentiation program to which a particular cell or cell lineage commits in the course of development. Such programs of differentiation require the timely expression of some genes and the silencing of others, with the result that different cells develop particular morphological, biochemical, and physical features in addition to those general housekeeping functions required for survival of all cells.

Specialized functions of cells and their arrangement into tissues and organs provides the whole organism with mechanisms to cope with a changing and often hostile environment in ways that ensure survival of the individual and perpetuation of the species. The complex functions of organ systems that are discussed in subsequent chapters require precise coordination of the activities of the individual cells of which they are composed. Such coordination is critically dependent upon an exchange of information between cells, between cells and their environment, and between the organism and its environment. Control of cellular activity has two separate but closely related aspects; one aspect relates to determining the complement of the "machinery" that a cell has available to carry out a particular task (i.e., what genes are expressed and to what degree), and the second aspect relates to governing the rate at which the machinery operates to perform that task.

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Get Rid of Gallstones Naturally

Get Rid of Gallstones Naturally

One of the main home remedies that you need to follow to prevent gallstones is a healthy lifestyle. You need to maintain a healthy body weight to prevent gallstones. The following are the best home remedies that will help you to treat and prevent gallstones.

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