The Monera Kingdom is composed of simple, single-celled organisms. Scientists sometimes separate this into two kingdoms, with one kingdom being the Archae Kingdom (which covers all organisms that live in extreme environments, like hot springs) and the Bacteria Kingdom. Within bacteria, major phyla include cyanobacteria (which make their food vita photosynthesis), proteobacteria (which get their food from nitrogen, in a primitive form of photosynthesis) and chlamydiae (which parasitically attach themselves to the cells of other organisms).
Like the Monera Kingdom, organisms in the Protista Kingdom are also single cell, but their cells are more complex due to the presence of a cell nucleus. One way in which protist phyla are organized is based upon how the organisms move; for example, there is the ciliophora phylum (which move using hair-like organelles on the exterior membrane) and the zoomastigophora phylum (which move using whip-like projections called flagellate). Like Kingdom Monera, Kingdom Protista also subdivided based on food source, such as with the apicomplexa phylum, whose organisms are parasites.
All organisms in the Fungi Kingdom are multicellular, and, despite their similarities to plants, they must get their food source from another organism. Fungi phyla are classified based on how the organism reproduces. For example, fungi in the zygomycota phylum reproduce by fusing two hyphae (a fungi's filament root strucutre) into a zygosporangium, which is a thick, wall-like structure. Organisms in the ascomycota phylum reproduce when hyphae fused together to produce a fruit called a ascocarp.
Organisms in the Plantae Kingdom are all multicellular organisms that produce their food via photosynthesis. Plant phylum are grouped first based on whether or not they are vascular (meaning if the plant has tissues for transporting water and minerals) and them, within vascular plants, whether or not they use seeds for reproduction. An example of a non-vascular phylum includes bryophyta (which is the phylum for mosses), a vascular phylum that does not produce seeds includes polypodiophyta (which is where ferns are classified) and a vascular plant phylum that produces seeds includes pinophyta (conifer trees).
Due to its diversity, the Animalia Kingdom has the largest number of phyla, with around 40. Because most animals reproduce sexually and are heterotrophos (meaning they rely on other organisms for food), animal phyla are generally classified based on body shape. For example, all mammals and other complex animals (like fish and reptiles) are in the chordata phylum because they have a nervous system and some form of exterior symmetry. The other animal phyla are primarily different types of worms, insects and sponges, such as the echinodermata phylum, which consists of organisms with radial symmetry.