How are living beings classified?
The current classification of living beings includes three domains and seven kingdoms. Domains group living beings by their cellular characteristics. The kingdoms are grouped by their evolutionary relationship. The classification system of living beings is structured as follows:
1. Domain Eukaryacontains five kingdoms, which are:
Kingdom Animalia
Kingdom Plantae
Kingdom Fungi
Kingdom Protozoa
Kingdom chromista or chromist
2. Bacteria Domaincontains the bacteria kingdom.
3. Domain Archaeacontains the kingdom archaea.
Living beings are all organisms with complex structures that are born, grow, reproduce and die. Given their variety and complexity, they are classified into various taxonomic categories for study.
In many parts of the world, Robert Whittaker’s classification system, which grouped living beings into five kingdoms (Monera, Fungi, Protista, Plantae and Animalae), continues to be used incorrectly. However, the correct (and current) model is the three domains model, proposed by Carl R. Woese in 1977.
Domain Eukarya
The Dominion Eukarya It is made up of all living beings that have eukaryotic cells, which have a differentiated nucleus, protected with a membrane and an organized cytoplasm. Some eukaryotes have mitochondria, organelles that generate energy.
The Eukarya domain is considered the most important, since the best-known kingdoms derive from it: Animalia, Plantae, Fungi, Chromista and Protozoa.
Kingdom Animalia
It is made up of all multicellular animals or organisms that develop from a zygote. They are classified into two large groups:
Vertebrates: They have a bone structure (fish, amphibians, birds, reptiles and mammals)
Invertebrates: They lack vertebrae (arthropods, mollusks, poriferans, cnidarians, echinoderms, flatworms, nematodes and annelids).
Kingdom Features Animalia
Their reproduction can be sexual (like most organisms in this kingdom) or asexual, as is the case of porifera (sea sponges) or other organisms. Their nutrition is heterotrophic, that is, they depend on other organisms to live. Their metabolism is aerobic, they require oxygen to live. They are symmetrical: their structure starts from an axis and is divided into two equal parts. They can move, either permanently (like humans) or temporarily, like corals. , which when they reach adulthood they stop moving.
Examples from the kingdom Animalia
The golden crucian fish (Carassius auratusThe Andean condor (Vultur gryphus).The squid (TeuthidaI had it solitary (Taenia solium.
The human being (homo sapiens).
See also Kingdom Animalia.
Kingdom Plantae
It is made up of all plants, which are multicellular eukaryotic organisms. In turn, the kingdom Plantae It has two large groups:
Non-vascular plants: They lack a nutrient transport system. They have no roots, stems or leaves.
Vascular plants: They have a differentiated vascular tissue, and have roots, stems and leaves.
Kingdom Features Plantae
They are autotrophic organisms, that is, they generate their own food (through photosynthesis). They cannot move. Their metabolism is aerobic: they breathe oxygen and expel carbon dioxide. They can have seeds or lack them. They can have flowers or lack them. they.
Examples from the kingdom Plantae
Ferns (filcopsidae). Orchids (OrchidaceaeThe orange tree or orange tree (Citrus × sinensis).
See also Kingdom Plantae
Kingdom Fungi
to the kingdom Fungi All mushrooms, yeasts and molds belong, which are multicellular organisms that generally develop in humid and aquatic environments. It is classified into three types:
Symbiotes: They are organisms that have a mutually beneficial relationship with other organisms.
Saprophytes or decomposers: They feed on the remains of other decomposing living beings.
Parasites: They feed on the organic matter generated by other living beings.
Kingdom Features Fungi
They reproduce asexually, using spores. They feed by pinocytosis or phagocytosis, breaking down compounds into micromolecules. Some organisms from the fungi kingdom are edible, such as certain types of mushrooms and mushrooms.
Examples from the kingdom Fungi
The yeast used in baking to create sourdoughs.The fungus Candidawhich causes infections in the skin and mucosa of humans.
See also: Kingdom Fungi
Kingdom Protozoa (protozoans)
The kingdom protozoa includes all eukaryotic organisms that cannot be considered animals, plants or fungi.
Kingdom Features protozoa
They are unicellular eukaryotic beings. Their nutrition can be heterotrophic, autotrophic or through photosynthesis. They have the capacity to move. Their reproduction is asexual. Their metabolic process is aerobic, they require oxygen to live. They do not have a cell wall, so their shape is changing.
Examples of the kingdom Protozoa
Amoeba or amoeba, the parasite that causes amoebiasis or amoebiasis. Trypanosoma (Euglenozoa), an intracellular parasite. Giardia (Metamonada), the parasite that causes the disease giardiasis.
Kingdom Chromist (chromists)
The kingdom chromista or chromista is made up of unicellular algae. This means that living beings in the chromatic kingdom cannot form tissues among themselves, but they are capable of photosynthesis.
Kingdom Features Chromist:
Its organization is unicellular. Its cells are eukaryotic. They can reproduce sexually or asexually. Its diet can be of different types. Its mobility is varied.
Examples from the Chromista kingdom
Brown algae, which usually live on rocky coasts. Diatom algae, which are found anywhere where water exists (seas, rivers, lakes and humid forests).
It may interest you; Eukaryotic cell
Domain or superkingdom Bacteria
The Bacteria domain is made up of prokaryotic organisms, that is, organisms whose cells lack a differentiated nucleus. For now, all beings in this domain belong to the bacteria kingdom.
Kingdom Bacteria
Beings from the bacteria kingdom do not have a nucleus or organelles inside the cell.
Characteristics of the Bacteria kingdom
Their DNA is called nucleoid, and is found in the cytoplasm of their only cell. They lack locomotion, some have organelles to move and others remain immobile. Their reproduction is asexual and they require the duplication of their genetic material to perpetuate themselves. Bacteria are pleomorphic organisms, that is, the same species can take several forms.
Examples from the kingdom Bacteria
The Escherichia coliwhich is found in the human digestive tract. Idonella sakaiensis, a bacteria that has the property of degrading plastic.
Dominion or superkingdom Archaea
It includes unicellular prokaryotic organisms without a differentiated nucleus, like bacteria. However, these are living beings with genetic and metabolic characteristics closer to eukaryotic organisms, although their evolutionary route is completely different. They can be present in ocean water, in different types of soil and even in the human digestive tract. The domain or superkingdom Archaea contains the kingdom Arquaea.
Kingdom Archaea
The microorganisms of the kingdom Archaea They have unique characteristics that place them in an intermediate place between the domains Eukarya and Bacterium.
Kingdom Features Archaea
They have a very wide nutritional variety: they feed on hydrogen, sugars or ammonia. They can use carbon or sunlight to obtain energy. They reproduce asexually, after duplicating their DNA. There are no known pathogenic archaea: their form of biological interaction is not harmful for other organisms.
Examples from the kingdom Archaea
The Mhetanosarcinaa type of archaea that produces methane. Ignicoccusan archaea that lives in marine hydrothermal vents.
See also