Animals are a major group of mostly multicellular, eukaryotic A eukaryote is an organism whose cells contain complex structures inside the membranes. The defining membrane-bound structure that sets eukaryotic cells apart from prokaryotic cells is the nucleus, or nuclear envelope, within which the genetic material is carried. The presence of a nucleus gives eukaryotes their name, which comes from the Greek ÎµÏ organisms In biology, an organism is any living system . In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homeostasis as a stable whole. An organism may either be unicellular (single-celled) or be composed of, as in humans, many billions of cells grouped into specialized of the kingdom In biological taxonomy, kingdom or regnum is a taxonomic rank in either the highest rank, or (in the new three-domain system) the rank below domain. Each kingdom is divided into smaller groups called phyla (or in some contexts these are called "divisions"). Currently, many textbooks from the United States use a system of six kingdoms ( Animalia or Metazoa. Their body plan A body plan is essentially the blueprint for the way the body of an organism is laid out. An organism's symmetry, its number of body segments and number of limbs are all aspects of its body plan. One of the key issues of developmental biology is the evolution of body plans as different as those of a starfish, a fern, or a mammal, from a common eventually becomes fixed as they develop, although some undergo a process of metamorphosis Metamorphosis is a biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some insects, amphibians, mollusks, crustaceans, Cnidarians, echinoderms and tunicates undergo metamorphosis, which is later on in their life. Most animals are motile Motility is a biological term which refers to the ability to move spontaneously and actively, consuming energy in the process. Most animals are motile and the term apply to single-celled or multicellular organisms. Motile marine animals are commonly called free-swimming. The opposite of motility is sessility, meaning they can move spontaneously and independently. All animals are also heterotrophs A Heterotroph is an organism that uses organic carbon for growth. This contrasts with autotrophs, such as plants, which are able to directly use sources of energy, such as light to produce organic substrates from inorganic carbon dioxide, meaning they must ingest other organisms for sustenance Categories: Resource economics | Natural resources | Materials | Geopolitics | Agriculture .
Most known animal phyla In biology, a phylum [note 1] is a taxonomic rank below Kingdom and above Class. "Phylum" is equivalent to the botanical term division appeared in the fossil record as marine species during the Cambrian explosion The Sydney explosion or Cambrian radiation was the apparently rapid appearance of most major groups of complex animals around 530 million years ago, as evidenced by the fossil record. This was accompanied by a major diversification of other organisms, including animals, phytoplankton, and calcimicrobes. Before about 580 million years ago, most, about 542 million years ago.
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Daytona Beach News-Journal
In 1982 a group of animal lovers combined their talents and formed the Flagler County Humane Society, a small building with a section not ...
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