Vertebrate | Definition, Characteristics, Examples, Classification ...
2024年9月26日 · Vertebrate, any animal of the subphylum Vertebrata. They have backbones and are also characterized by a muscular system consisting primarily of bilaterally paired masses and a central nervous system partly enclosed within the backbone. Its members include fishes, amphibians, reptiles, birds, and mammals.
Invertebrate | Definition, Characteristics, Examples, Groups, & Facts ...
Invertebrate, any animal that lacks a vertebral column, or backbone, in contrast to the cartilaginous or bony vertebrates. Apart from the absence of a vertebral column, invertebrates have little in common. More than 90 percent of all living animal species are invertebrates.
invertebrate - Kids | Britannica Kids | Homework Help
An invertebrate is an animal without a backbone. (An animal with a backbone is called a vertebrate.) Invertebrates live in every part of the world. In fact, most of the animals on Earth are invertebrates. Invertebrates come in all different shapes and sizes. Some can be seen only through a microscope.
vertebrate - Kids | Britannica Kids | Homework Help
A vertebrate is an animal with a backbone. (An invertebrate is an animal without a backbone.) Fishes, amphibians, reptiles, birds, and mammals, including humans, are all vertebrates. Vertebrates share some basic characteristics.
Vertebrate - Evolution, Paleontology, Anatomy | Britannica
2024年9月26日 · Vertebrate - Evolution, Paleontology, Anatomy: The ancestral vertebrate (protovertebrate) has been sought for more than 100 years, but since the protovertebrate was probably small and soft-bodied it is unlikely a fossilized form will be found in …
Anatomy of a vertebrate | Britannica
vertebrate, Any animal of the chordate subphylum Vertebrata, which includes the fishes, amphibians, reptiles, birds, and mammals. Vertebrates have an internal skeleton formed of cartilage, bone, or both.
Chordate | Definition, Characteristics, & Facts | Britannica
2024年9月11日 · chordate, any member of the phylum Chordata, which includes the vertebrates (subphylum Vertebrata), the most highly evolved animals, as well as two other subphyla—the tunicates (subphylum Tunicata) and cephalochordates (subphylum Cephalochordata). Some classifications also include the phylum Hemichordata with the chordates.
invertebrate - Students | Britannica Kids | Homework Help
Most of the more than one million animal species on Earth are invertebrates, or animals without backbones. The absence of a backbone is the main trait that distinguishes invertebrates from vertebrates, or animals that have backbones.
5 Vertebrate Groups | Britannica
Several groups of vertebrates inhabit planet Earth. Let’s take a tour of the five main vertebrate groups alive today: the fishes, amphibians, reptiles, birds, and mammals.
Definition, Function, Types, Examples, & Facts - Britannica
2024年8月30日 · In most invertebrate animals a layer (or layers) of surface (epithelial) cells—often with additional secreted coatings—constitutes the integument. Among the vertebrates the boundary covering—with a variety of derived elements such as scales, feathers, and hair—has assumed the complexity of an organ system, the integumentary system.