公共英语一级考试阅读范文(11)

牛课网 考试宝典 更新时间:2024-05-15 18:37:41

全国公共英语一级考试 公共英语四六级考试官网 公共英语PETS是四六级考试吗

为了帮助大家更好的复习公共英语一级考试,公共英语等级考试网为大家整理了公共英语一级考试阅读范文的资料,欢迎大家前来我站学习。以下是公共英语一级考试阅读范文的内容,希望会对大家有多帮助。

Plankton

Scattered through the seas of the world are billions of tons of small plants and animals called plankton. Most of these plants and animals are too small for the human eye to see. They drift about lazily with the currents, providing a basic food for many larger animals.

Plankton has been described as the equivalent of the grasses that grow on the dry land continents, and the comparison is an appropriate one. In potential food value, however, plankton far outweighs that of the land grasses. One scientist has estimated that while grasses of the world produce about 49 billion tons of valuable carbohydrates each year, the sea's plankton generates more than twice as much.

Despite its enormous food potential, little effect was made until recently to farm plankton as we farm grasses on land. Now marine scientists have at last begun to study this possibility, especially as the sea's resources loom even more important as a means of feeding an expanding world population.

No one yet has seriously suggested that "planktonburgers" may soon become popular around the world. As a possible farmed supplementary food source, however, plankton is gaining considerable interest among marine scientists.

One type of plankton that seems to have great harvest possibilities is a tiny shrimplike creature called krill. Growing to two or three inches long, krill provide the major food for the great blue whale, the largest animal ever inhabit the Earth. Realizing that this whale may grow to100 feet and weigh 150 tons at maturity, it is not surprising that each one devours more than one ton of krill daily.

编辑推荐:

公共英语一级考试阅读范文汇总

考试宝典安装说明

宝典适用于手机、电脑、平板,您可安装客户端或在浏览器使用。

电脑版

手机版

网页版

考试宝典咨询
服务热线

TEL:029-88699698