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.
How are organisms classified to the species level? A hierarchical system is used for classifying organisms to the species level. This system is called taxonomic classification. The broadest classifications are by domain and kingdom; the most specific classification is by genus and species. The hierarchical groupings in between include phylum, class, family, and order. Species are the basic unit of classification.