The Animal is a multicellular organism that, in general, has the capacity for movement and sensitivity. It is characterized by having many eukaryotic cells, lacking a cell wall and photosynthetic pigments, and in addition to being heterotrophic, its nutrition is carried out mainly by ingestion through an internal cavity, some animals feed on other living beings, and their reproduction it is usually sexual.
The morphology of an animal is very diverse, it exists both microscopically (a worm) and large (a whale), as well as its anatomy is very different between species.
An animal can live in water (aquatic) or on land (terrestrial). The dinosaur is known as the most extinct animal on this planet, in the same way man is considered an animal, but with the difference of having the use of reason and thought.
There are thousands of species of animals, where their most common division is that of invertebrates and vertebrates (absence or presence of vertebral column). The former are made up of rotifers, sponges, cnidarians, flatworms, tube worms, annelids, mollusks, arthropods (crustaceans, myriapods, insects and arachnids) and echinoderms; and the latter are represented by fish, amphibians, reptiles, birds and mammals.
Animals constitute a fundamental link in the trophic chains and are essential in maintaining the ecological balance, since when they die they become part of the soil humus and then when they decompose they are absorbed by the plants for their nutrition and reproduction.
Since ancient times, animals have been used by man as a means of transport, in the manufacture of clothing and footwear (hides and leather), in food (meat, milk, etc.), for aesthetic and recreational purposes (aquariums, zoos, etc.), and in health, they help to make serums and vaccines, and are the object of study to test medicines for man. However, they have a negative part because many are disease transmitters.
The term animal also refers to the very ignorant, rude and violent person, who uses brute force a lot. For example: What animal is your father! Don't be such an animal eating that way .
