Text 3
Most growing plants contain much more water than all other materials combined. C. R. Bames 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. Certainly 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 plants and are built into essential plant materials while in a dissolved state.
The carbon dioxide (CO2) 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 wood
A. a plant efficiently utilizes most of the water it absorbs
B. carbon dioxide is the essential substance needed for plant development
C. a plant needs more water than is found in its composition
D. the stronger the wind, the more the water vapor loss'
Text 3
Most young people enjoy some form of physical activity. It may be walking, cycling or swimming, or in winter, skating or skiing; it may be a game of some kind: football, hockey, golf, or tennis; it may be mountaineering.
Those who have a passion for climbing high and difficult mountains are often looked upon with astonishment. Why are men and women willing to suffer cold and hardship, and to take risks on high mountains This astonishment is caused probably by the difference between mountaineering and other forms of activity to which men give their leisure.
Mountaineering is a sport and not a game. There are no man - made rules, as there are for such games as golf and football. There are, of course, rules of a different kind which it would be dangerous to ignore, but it is this freedom from man- made rules that makes mountaineering attractive to many people. Those who climb mountains are free to use their own methods.
If we compare mou
A. Mountaineering
B. Mountain Climbers
C. Mountaineering Is Different from Golf and Football
D. Mountaineering Is More Dangerous than Other Sports
Text 3 Most young people enjoy some form of physical activity. It may be walking, cycling or swimming, or in winter, skating or skiing; it may be a game of some kind: football, hockey, golf, or tennis; it may be mountaineering. Those who have a passion for climbing high and difficult mountains are often looked upon with astonishment. Why are men and women willing to suffer cold and hardship, and to take risks on high mountains This astonishment is caused probably by the difference between mountaineering and other forms of activity to which men give their leisure. Mountaineering is a sport and not a game. There are no man - made rules, as there are for such games as golf and football. There are, of course, rules of a different kind which it would be dangerous to ignore, but it is this freedom from man- made rules that makes mountaineering attractive to many people. Those who climb mountains are free to use their own methods. If we compare mountaineering and other more famil
A. uniform
B. activity
C. rules
D. skills
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