首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Information about tiger sharks is rare in books so most of this paper about sharks will be in general. The Tiger Sharks’ Latin n
Information about tiger sharks is rare in books so most of this paper about sharks will be in general. The Tiger Sharks’ Latin n
admin
2010-04-30
39
问题
Information about tiger sharks is rare in books so most of this paper about sharks will be in general. The Tiger Sharks’ Latin name is Galeocerdo Cuvier. Sharks are a member of the fish family. There are over 350 species of sharks. Sharks can be as big as 49 feet long (whale shark) and as short as 6 inches (cigar shark). Sharks’ bodies do not have bones, but have cartilage (软骨) instead. They have pointed heads with five gills (鳃) behind it. Sharks have very sharp teeth that are replaced whenever they lose teeth. Sharks’ skin can be reddish brown, bronze, metallic blue or nearly black, although most of them are gray. Some have spots, bands and marbling. Their skin is leathery (粗糙) and covered with small pointed scales (鳞) which are so sharp that if petted in the opposite direction can actually hurt your hand.
Sharks have great senses. Their eyes are sensitive and can even see in dim light. Their sense of smell is outstanding. They also have senses that humans do not. Sharks can feel when other things are around them. Also, they have organs on their snouts (鼻子) which tell them when other fish are around. Sharks are known to eat every creature in the sea including their own kind. Some sharks eat only plants and plankton (浮游生物). Others prefer live food. People have found very unusual things in sharks’ stomachs such as hooves of cows, horses, dogs, cats, goats and human corpses.
Unlike bony fish which lay hundreds of eggs at one time, sharks’ litters are much smaller. Some sharks have as few as two offspring at a time. Bony fish babies are born small and puny. Shark "pups" are born fully developed and are ready to eat the foods that full-grown sharks eat.
Some of sharks’ behavior is interesting and understood. Other behaviors are still mysterious. For example, sharks attack when they are hungry. But why they attack when they are not hungry, we do not know. They may attack for defense, because they think humans are food, because they smell blood or because they smell or sense chemicals that are interesting to them. While people may think that all sharks are dangerous, only about 30 species are considered dangerous, including the Tiger Shark. Even when sharks do attack, the victims usually do not die anyway.
Sharks are found in all of the world’s oceans although most of them prefer to live in tropical waters. A very few species live in waters as cold as the Antarctic Ocean. Sharks live at all depths of the oceans. Because sharks are so adaptable there are many of them all around the world, living in all of our oceans.
Here are some interesting facts about tiger sharks:
Shark eggs have strings attached to them. The strings hook onto corals or seaweed so the egg will not drift off. All baby sharks are called pups. Sharks are one of the oldest species of animals and have been on earth for about three million years.
Sharks’ only natural predator (猎食者) is sharks.
Unlike bony fish, sharks do not have air bladders (囊) and so if they stop swimming , they will sink to the bottom.
The largest organ in the shark’s body is its liver. Sharks can survive without food for long periods of time because they can live off the oil of their fiver.
People use many products that come from sharks such as oil, vitamins, fertilizer and leather. Some people also like to collect shark teeth and jaws. Shark meat is becoming a more popular food in the United States.
Tiger sharks can ______ when other things are around them because they have ______.
选项
答案
feel/sense,sensitive organs/great senses
解析
参看文章第二段前六句。
转载请注明原文地址:https://kaotiyun.com/show/ETOK777K
0
大学英语六级
相关试题推荐
Whichofthefollowingcanreflecttheever-changingethnicstructureofAmerica?Theauthorofthepassagewantstotellthat
Shynessisthecauseofmuchunhappinessforagreatmanypeople.Shypeopleareanxiousand(36)______;thatis,theyareexces
Acalorieisaunitofenergyassociateswithanythingcontainingenergyexceptfood.Expertssuggestthehighestnumberoffat
A、Inahospital.B、Inaclinic.C、Inahospitalward.D、Inaninjectionroom.AW:Tellmeyoursymptom,please.M:Well,I’yeb
A、Leavethehotelthenextmorning.B、Askthehotelclerkforhisroomkey.C、Stayinthehotelforatleasttwonights.D、Compl
Theworkersfollowedthesamescheduleseachworkday,andrarely____________(他们违背这个常规).
Althoughitisusuallyunclearwhostartsthegossip,peopletendtobelieveit.ThestoryofJasonshowsthatalthoughgossips
A、Thereisasignof"greenhand"insidethecar.B、Therearetwosetsofbrakesinsidethecar.C、Itisonlybigenoughtohold
A、Heisseriouslyillandstillinhospital.B、MarywilldohisworkinsteadC、Morrisonishisdoctor.D、Hewillgotoworktomo
IfIhadnotseenitwithmyowneyes,I__________________(根本不会相信的).
随机试题
用邻二氮杂菲测铁时所用的波长属于()。
根据医疗文件书写要求,下列哪项不妥()。
积聚的诊断依据包括()
某工程公司同银行签订贷款合同,合同中有银行要求企业定期向银行提交财务报表,不准出售较多资产,按时纳税,限制租赁的规模等内容的条款,这些条款属于______。
由于短期移动平均线较长期移动平均线更易于反应行情价格的涨跌,所以一般又把短期移动平均线称为快速MA,长期移动平均线则称为慢速MA。()
连接有机体和无机环境的两个重要环节是()。
李湘是一个十分聪明的学生,他的最大特点就是贪玩,学习不用功。每次考试前他都存有侥幸心理,希望能够靠运气过关。这次期末考试他考得不理想,他认为这次是自己的运气太差了。请运用韦纳的归因理论来分析:如不正确,正确的归因应该是怎样的?
一、铁路常旅客会员积分累积规则(1)会员购买列车车票,并实际乘车到站后获得积分累积。(2)国际列车车票、积分兑换的奖励车票、列车补票、到站补票、非实名制车票暂不参与积分累积。(3)乘车积分=票面价格×5,积分以“分”为单位,按四舍五入取整计算。(4
级数(a>0)().
ThirstforOilWorldwideeveryday,wedevourtheenergyequivalentofabout200millionbarrelsofOil.Mostoftheenergy
最新回复
(
0
)