首页
登录
职称英语
Several hundred million years ago, plants similar to modern ferns covered va
Several hundred million years ago, plants similar to modern ferns covered va
游客
2025-04-03
28
管理
问题
Several hundred million years ago, plants similar to modern ferns covered vast stretches of the land. Some were as large as trees, with giant fronds bunched at the top of trunks as straight as pillars. Others were the size of bushes and formed thickets of me undergrowth. Still others lived in the shade of giant club mosses and horsetails along the edges of swampy lagoons where giant amphibians swam.
A great number of these plants were true ferns, reproducing themselves without fruits or seeds. Others had only the appearance of ferns. Their leaves had organs of sexual reproduction and produced seeds. Although their "flowers" did not have corollas these false ferns(today completely extinct)ushered in the era of flowering plants. Traces of these floras of the earliest times have been preserved in the form of fossils. Such traces are most commonly found in shale and sandstone rocks wedged between coal beds.
Today only tropical forests bear living proof of tile ancient greatness of ferns. The species that grow there are no longer those of the Carboniferous period, but their variety and vast numbers, and the great size of some, remind us of the time when ferns ruled the plant kingdom. [br] What does the passage mainly discuss?
选项
A、Plant reproduction.
B、An ancient form of plant life.
C、How to locate fossils.
D、Tropical plant life.
答案
B
解析
主旨题。这篇文章主要讨论的就是远古时代的一种植物,故答案选D;A“植物繁殖”,如果以此为标题,文章说的就应该是植物是怎样繁殖的,那么说的植物就应该是很多种不同种类的植物是怎样繁殖的。
转载请注明原文地址:https://tihaiku.com/zcyy/4024887.html
相关试题推荐
Thegovernmenthaspromisedtooffer10millionofemergencyfoodaidtohelp___
Thisnewbookhasreceivedseveralreviewssinceitspublication;butnoneofth
Whydosomedesertplantsgrowtallandthinlikeorganpipes?Whydomostt
Whydosomedesertplantsgrowtallandthinlikeorganpipes?Whydomostt
Whydosomedesertplantsgrowtallandthinlikeorganpipes?Whydomostt
Thirty-onemillionAmericansareover60yearsofage,andtwenty-ninemilli
Thirty-onemillionAmericansareover60yearsofage,andtwenty-ninemilli
OnehundredandthirteenmillionAmericanshaveatleastonebank-issuedcre
OnehundredandthirteenmillionAmericanshaveatleastonebank-issuedcre
OnehundredandthirteenmillionAmericanshaveatleastonebank-issuedcre
随机试题
Anyhousewifewhowenttothenewsupermarketwishedtobetheluckycustomerwh
Yearsago,manyofthemachineswereoperated______butnowtheyareoperatedb
[originaltext]HuangYiworksforacompanythatsellsfinancialsoftwareto
观光旅游的特点有( )。A.参与性差 B.“走马观花” C.时间与金钱支出
2011年12月,中国加入世界贸易组织十周年高层论坛举行,胡锦涛主席在讲话中指出
在计算利息额时,按一定期限,将所生利息加入本金再计算利息的计息方法是()。A.
化疗前护士要准确测量患者的体重,其目的是A.精确计算输液量 B.精确计算患者的
腹外疝的常见原因不包括()。A.腹部切口愈合不良 B.老年人慢性便秘 C.腹
现代政府预算应具备的突出特征是()。A.预测性 B.法律性 C.集中性 D
宋初为强化中央集权,在皇宫中设置的审判复核机关为()。 A.审刑院B.大理
最新回复
(
0
)