| 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) The mineral elements will not be absorbed by the plant unless they are dissolved in its root. B. (B) The woody stems contain more water than the leaves. C. (C) Air existing around the leaf is found to be saturated. D. (D) Only part of the carbon dioxide in the plants is synthesized. [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. to form sugars B. to derive energy from light C. to preserve water D. to combine carbon dioxide with water [填空题]The United States spend much more money on programs to prevent diseases than on ______.
[填空题]According to the passage, people are much more likely to get heart attacks because of ______.
[填空题]According to critics, it will cost much more spending in our pursuit of______.
[填空题](41)Orientation
Yellowstone is much more than hot ground and gushing steam. Located astride the Continental Divide, most of the park occupies a high plateau surrounded by mountains and drained by several rivers. Park boundaries enclose craggy peaks, alpine lakes, deep canyons, and vast forests. In 1872, Yellowstone became the world’s first national park, the result of great foresight on the part of many people about our eventual need for the solace and beauty of wild places. (42) When to Go More than half of the 3 million annum visitors come in July and August. In September and early October, the weather is good, the visitors few, and the wildlife abundant. In May and June, you can see newborn animals, but the weather may be cold, wet, and even snowy. Between about No-vember 1 and May 1 most park roads are closed to vehicles. (43) Getting There (44) How to Visit The 142-mile (228.5-kilometer) Grand Loop Road forms a figure eight [填空题]
(41)Orientation 我来回答: 提交
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