| Most growing plants contain much more
water than all other materials combined. C. R. Barnes has suggested that it is
as proper to term the plant a water structure as to call a house composed mainly
of brick a brick building. Certain it is that all essential processes of plant
growth and development occur in water. The mineral elements from the soil that
are usable by the plant must be dissolved in the soil solution before they can
be taken into the root. They are carried to all parts of the growing plant and
are built into essential plant materials while in a dissolved state. The carbon
dioxide from the air may enter the leaf as a gas but is dissolved in water in
the leaf before it is combined with a part of the water to form simple
sugars—the base material from which the plant body is mainly built. Actively
growing plant parts are generally 75 to 90 perce A. (A) forming sugars B. (B) sustaining woody stems C. (C) keeping green D. (D) producing carbon dioxide [单项选择]Most growing plants contain much more water than all other materials combined. C. R. Barnes has suggested that it is as proper to term the plant a water structure as to call a house composed mainly of brick a brick building. Certain it is that all essential processes of plant growth and development occur in water. The mineral elements from the soil that are usable by the plant must be dissolved in the soil solution before they can be taken into the root. They are carried to all parts of the growing plant and are built into essential plant materials while in a dissolved state. The carbon dioxide from the air may enter the leaf as a gas but is dissolved in water in the leaf before it is combined with a part of the water to form simple sugars—the base material from which the plant body is mainly built. Actively growing plant parts are generally 75 to 90 percent water. Structural parts of plants, such as woody stems no longer actively growing, may have much less water than growing tissues.
A. forming sugars B. sustaining woody stems C. keeping green D. producing carbon dioxide [简答题]Americans are much more likely than citizens of other nations to believe that they live in a meritocracy, i.e. Government by people selected according to merit. But this self-image is a fantasy: America actually stands out as a the advanced country in which it matters most who your parents were, the country in which those born on one of society’s lower rungs have the least chance of climbing to the top or even to the middle.
And if you ask why America is more class-bound in practice than the rest of the Western world, a large part of the reason is that our government falls down on the job of creating equal opportunity.
The failure starts early: in America, the holes in the social safety net mean that both low-income mothers and their children are all too likely to suffer from poor nutrition and receive inadequate health care. It continues once children reach school age, where they encounter a system in which the affluent send their kids to good, well-financed public schools o
[简答题]Eating more than 18 ounces of red meat per week ups your risk of colorectal cancer. Its risk also rises by 40% with every three ounces serving of process meat eating per day.
[单项选择]He was much more thorough in his studies than the rest of his class and it was for this reason （）he made such great progress.
A. why B. how C. that D. for 我来回答: 提交
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