首页
登录
职称英语
Sea otters dwell in the North Pacific. They are the largest of the mustelids,
Sea otters dwell in the North Pacific. They are the largest of the mustelids,
游客
2023-12-17
26
管理
问题
Sea otters dwell in the North Pacific. They are the largest of the mustelids, a group which also includes freshwater otters, weasels, and badgers. They are from four to five feet long, and most weigh from 60 to 85 pounds. Large males may weigh 100 pounds or more.
Unlike most marine mammals, such ms seals or dolphins, sea otters lack a layer of blubber, and therefore have to eat up to 30% of their body weight a day in clams, crabs, fish, octopus, squids, and other delicacies to maintain body heat. Their voracious appetites do not create food shortages, though, because they are picky eaters, each animal preferring only a few food types. Thus no single type of fond source is exhausted. Sea otters play an important environmental role by protecting forests of seaweed called kelp, which provide shelter and nutrients for many species. Certain sea otters feast on invertebrates like sea urchins and abalones that destroy kelp.
Sea otters eat and sleep while floating on their backs, often on masses of kelp. They seldom come on shore. Sea otters keep warm by means of their luxuriant double-layered fur, the densest among animals. The soft outer fur forms a protective cover that keeps the fine underfur dry. One square inch of underfur contains up to 1 million hairs. Unfortunately, this essential feature almost led to their extinction, as commercial fur hunters drastically reduced their numbers.
Under government protection, the sea otter population has recovered. While elated by the otters return, scientists are concerned about the California sea otter population growth of 5% a year, lagging behind the 18% a year rate among Alaska otters. Sea otters are extremely sensitive to pollution. In 1989 up to 5,000 sea otters perished when the Exxon Valdez spilled oil in Prince William Sound, Alaska. [br] Which of the following best describes sea otters’ relationship with kelp forests according to the passage?
选项
A、The kelp serves as food for the otter.
B、The otters protect the kelp by eating animals that destroy it.
C、The otters eliminate the kelp’s source of nutrients.
D、The kelp is destroyed when the otters build shelters.
答案
B
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3281935.html
相关试题推荐
ThelargestandsmalleststatesoftheUnitedStatesare______.A、AlaskaandRho
______hasbecometheworld’slargestexporteroffish.A、CanadaB、TheUnitedSta
[originaltext]Amassiveevacuationoftouristsinoneoftheworld’slargest
WhichisthelargestcityinScotland?A、Cardiff.B、Edinburgh.C、Glasgow.D、Manch
_________isthelargest________city.Ithasafinenaturalharbourandastri
ThelargestcityinAustraliais_____.A、AlaskaB、SydneyC、CanberraD、PerthBSy
______,oneofBritain’slargestports,rosetoworldwidefameinthe1960sast
______,locatedatthesouthernendofLakeMichigan,isthesecondlargestcity
ThelargestandsmalleststatesoftheUnitedStatesare______.A、AlaskaandRho
______isthelargest_______city.Ithasafinenaturalharbourandastriking
随机试题
增强enhance;heighten
[originaltext]M:Honey,thebasketballgameisabouttostart.Andcouldyoubr
[audioFiles]audio_etoefz_055(20051)[/audioFiles]A、Sheisalsoplanningtotrave
Tolearnwithsuccessisnotaverydifficulttaskofsomefundamentalprin
[originaltext]M:Willyoupleasefixthebuttonforme,dear?W:Oh,I’msobus
1、4
用于冬季室外计算温度在-10℃以下的地区的砖,要求吸水饱和后在-15℃的条件下,
某tRNA的反密码子为UGA,其相应识别的密码子是()A.UCC B.AC
A.柴胡 B.防风 C.秦艽 D.牛膝 E.板蓝根呈类圆柱形,残存茎基有
不能用生理性妊娠解释的是( )。A.血液处于高凝状态 B.红细胞沉降率下降
最新回复
(
0
)