When the walls of the excavations are to be kept vertical and in order to protect the safety of. workmen, the general public, this or other work or structures, or excavation walls, or pipe. installation including ma terials encountered in the excavation which have a tendency to slough.
Hierarchy of Living Things. Biological organization, or the hierarchy of life, is the hierarchy of complex biological structures and system that define life using a reductionistic approach. The traditional hierarchy, as detailed below, extends from atoms (or lower) to biospheres.
The series of terms in the sequence of biological organization from  the simplest to the most complex is cell, tissues, organs, systems,  and lastly the organism. This is thâ¦e way living things are  organized. 3 people found this useful.