Fish | Definition, Species, Classification, & Facts | Britannica
2024年11月19日 · Fish, any of approximately 34,000 species of vertebrate animals (phylum Chordata) found in the fresh and salt waters of the world. Living species range from the primitive jawless lampreys and hagfishes through the cartilaginous sharks, skates, and rays to the abundant and diverse bony fishes.
5 Groups of Vertebrates – Characteristics and Examples
2022年6月29日 · The five main groups of vertebrates are fish, amphibians, reptiles, birds, and mammals. There are actually more categories, since bony fish are separate from jawless fish (lampreys and hagfish), cartilaginous fish (sharks and …
Fish - Wikipedia
A fish (pl.: fish or fishes) is an aquatic, anamniotic, gill-bearing vertebrate animal with swimming fins and a hard skull, but lacking limbs with digits. Fish can be grouped into the more basal jawless fish and the more common jawed fish, the latter including all living cartilaginous and bony fish, as well as the extinct placoderms and ...
Fish – Definition, Examples, Characteristics - Science Notes and …
2024年5月21日 · Fish are aquatic vertebrates that typically have gills, fins, and a streamlined body. They inhabit diverse environments, from freshwater rivers and lakes to salty oceans and deep seas. Fish, like all vertebrates, possess a backbone or spinal column. This characteristic places them within the subphylum Vertebrata.
Fish - Classification, Jawless, Cartilaginous & Bony Fishes | Britannica
2024年11月21日 · Fishes are typically divided into three groups: superclass Agnatha (jawless fishes), class Chondrichthyes (cartilaginous fishes), and superclass Osteichthyes (bony fishes). The latter two groups are included within the infraphylum Gnathostomata, a category containing all jawed vertebrates.
Fish: Different Types, Definitions, Photos, and More
2023年1月3日 · Instead, there are 3 main classes, groups, or types of fish: bony fish (Osteichthyes), jawless fish (Agnatha), and cartilaginous fish (Chondrichthyes). Fish are the most diverse group among vertebrates, with over 33,000 different types of fish species.
Vertebrate - Wikipedia
Vertebrates span the Agnatha or jawless fish, and the jawed Gnathostomata. These include both the Chondrichthyes or cartilaginous fish and the Osteichthyes or bony fish. Among the latter are the Sarcopterygii or lobe-finned fish, which include the Tetrapoda [a] or limbed vertebrates.
Vertebrate - The Definitive Guide - Biology Dictionary
2021年2月13日 · Any vertebrate, classified under subphylum Vertebrata, is an animal with a backbone. This group consists of several broad classes: fish, amphibians, birds, reptiles, and mammals. The word vertebrate refers to the bony vertebral column.
Fish species and physical features | Britannica
fish, Any of more than 30,000 species of predominantly cold-blooded vertebrates found worldwide in fresh and salt water. Living species range from the primitive lampreys and hagfishes through the cartilaginous shark s, skates, and ray s to the abundant and diverse bony fishes.
12.8: Fish Structure and Function - Biology LibreTexts
Fish are aquatic, ectothermic vertebrates. Many structures in fish are adaptations for their aquatic lifestyle. For example, fish have a stream-lined body that reduces water resistance while swimming.