有关鲨鱼的介绍 (用英语)要用英语,字数不超过100,急用!
来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/23 22:05:32
有关鲨鱼的介绍 (用英语)要用英语,字数不超过100,急用!
有关鲨鱼的介绍 (用英语)
要用英语,字数不超过100,急用!
有关鲨鱼的介绍 (用英语)要用英语,字数不超过100,急用!
Sharks (superorder Selachimorpha) are fish with a full cartilaginous skeleton[1] and a streamlined body.They respire with the use of five to seven gill slits.Sharks have a covering of dermal denticles to protect their skin from damage and parasites and to improve fluid dynamics.[1] They have replaceable teeth.They are some of the world's most misunderstood predators,as they very rarely attack humans unless intimidated.
Sharks include species from the hand-sized pygmy shark,Euprotomicrus bispinatus,a deep sea species of only 22 centimetres (9 inches) in length,to the whale shark,Rhincodon typus,the largest fish,which grows to a length of approximately 12 metres (41 feet) and which,like the great whales,feeds only on plankton through filter feeding.The bull shark,Carcharhinus leucas,is the best known of several species to swim in both salt and fresh water (it is found in Lake Nicaragua,in Central America) and in deltas.[2]