ABSTRACT

The higher organisms have a hierarchical body plan in which the whole body

system is composed of the organ system, organs, tissues, cells, and subcellular

organelles, each of which is itself composed of various compartments

(Fig. 13.1). This highly organized compartmentalization is a sophisticated

means of housing biological systems according to their speciic functions, and

homeostasis is maintained in each compartment as a nonequilibrium open

system.