首页
登录
职称英语
About fifty years ago, plant physiologists set out to grow roots by themselv
About fifty years ago, plant physiologists set out to grow roots by themselv
游客
2025-02-03
36
管理
问题
About fifty years ago, plant physiologists set out to grow roots by themselves in solutions in laboratory flasks. The scientists found that the nutrition of isolated roots was quite simple. They required sugar and the usual minerals and vitamins. However, they did not require organic nitrogen compounds. These roots got along fine on mineral inorganic nitrogen. Roots are capable of making their own proteins and other organic compounds. These activities by roots require energy, of course: The process of respiration uses sugar to make the high energy compound ATP, which drives the biochemical reactions. Respiration also requires oxygen. Highly active roots require a good deal of oxygen.
The study of isolated roots has provided an understanding of the relationship between shoots and roots in intact plants. The leaves of the shoots provide the roots with sugar and vitamins, and the roots provide the shoots with water and minerals. In addition, roots can provide the shoots with organic nitrogen compounds. This comes in handy for the growth of buds in the early spring when leaves are not yet functioning. Once leaves begin photosynthesizing, they produce protein, but only mature leaves can "export" protein to the rest of the plant in the form of amino acids. [br] The scientists found what the isolated roots need is ______
选项
A、quite natural
B、sugar, minerals and vitamins
C、some rare vitamins
D、organic nitrogen compounds
答案
B
解析
见第一段第三句:They required sugar and the usual minerals and vitamins.所以选项B是答案。
转载请注明原文地址:https://tihaiku.com/zcyy/3940555.html
相关试题推荐
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
Aboutfiftyyearsago,plantphysiologistssetouttogrowrootsbythemselv
随机试题
Ifyouwanttolearnsometermsrelatedtoyourfield,youwillfindthisbookm
[originaltext]M:Mr.Jones,thisistheticketforyourflighttoBeijing.W:
[originaltext]M:Mr.Jones,thisistheticketforyourflighttoBeijing.W:
出任台湾省首任巡抚的是( )。A.沈应奎 B.刘铭传 C.邵友濂 D.唐
某女士,65岁,初次到社区卫生服务中心就诊。其主诉诊断高血压5年,一直遵医嘱服药
卖出看涨期权的目的包括()。A.获取价差收益 B.获取权利金收益 C.增加
基础心理学是研究()。 (A)正常成人心理现象的心理学基础学科 (B
男,40岁。感冒后,下唇及唇周皮肤出现成簇的针头大小的小水疱,破溃后结痂,局部灼
FIFIC系列合同中,下列选项中适用于《施工合同条件》的是()A.适用于传统的
采用敞口式(手掘式)顶管机时,应将地下水位降至管底以下不小于()处,并应采取措
最新回复
(
0
)