The Five Kingdoms Essay, Research Paper

The Five Kingdoms

Monera

This biological kingdom is composed of bacteria and cyanobacteria, one-celled (sometimes colonial) organisms whose cells lack a nuclear envelope, mitochondria, or plastids. They reproduce asexually through fission (splitting in two) and mainly gain their nutrition by absorbing it from their environment (though some species are chemoautotrophs or photosynthetic). This is the most primitive of the five kingdoms; it encompasses all the bacteria. Monerans are single-celled prokaryotic organisms.

Protista

This biologic kingdom is composed of eukaryotic organisms: unicellular and multicellular algae, slime molds, and unicellular or simple colonial protozoans. Protists obtain their nutrition via several methods, including photosynthesis, devouring other organisms, and absorption. Protists can reproduce sexually or asexually, and they can be sedentary or move with pseudopods, flagella, or cilia. There are over 55,000 known living species and over 35,000 known extinct species in this kingdom.

Fungi

This kingdom is composed of single-celled (sometimes multicellular), eukaryotic organisms. Protists are more complex than bacteria and include protozooans and some types of algae.Kingdom Fungi includes organisms such as slime molds, mushrooms, smuts, rusts, mildews, molds, stinkhorns, puffballs, truffles and yeasts. All are classified in this kingdom because they absorb food in solution directly through their cell walls and reproduce through spores. None conduct photosynthesis.

Plantae

The members of this kingdom are multicellular, eukaryotic organisms that (usually) conduct photosynthesis.

Animalia

The members of this kingom are complex, multicellular, eukaryotic organisms that digest food outside their cells and then absorb the digested nutrients. Animals must consume other organisms to obtain most of their nutrients.