up vote 3 down vote accepted. $\pi$ is the name of the constant relating the diameter and circumferance of a circle. It's a definition, a particular constant that we thought deserved a name. $e$ happens to be the name of a constant from a particular limit. Like $\pi$, we named it because we thought it would be useful. In Physics, many, many constants have names. Gravitational constants, expansional constants, electrical constants, etc. Each is useful, but somewhat arbitrarily chosen.
Bacteria: The Monera Kingdom Bacteria are classified into two groups: Eubacteria (true bacteria) and Archaebacteria (Ancient Bacteria). They are autotrophic. 28-1 Chapter 28: Microbiology. 28-2 Viruses Viruses are noncellular, nonliving particles and therefore are not included in the classification scheme.
The five kingdoms of living organisms are the kingdom Monera, the kingdom Protista, the kingdom Fungi, the kingdom Plantae and the kingdom Animalia.Viruses are not included in this classification and sometimes are said to belong to their own kingdom, the kingdom Virus.iving organisms are classified, going from the broader to the more specific category, into kingdom, phylum, class, order, family, genus and species (KPCOFGS can be used as a mnemonic). Kingdom is the broadest category each following category is a subcategory of the previous one.