题干

号称“世界爷”的巨杉,树高可达142米,影响水分输送到树梢的生理活动是(  )

A:光合作用

B:呼吸作用

C:蒸腾作用

D:吸收作用

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答案(点此获取答案解析)

C

同类题4

阅读下面两篇文言文,回答小题。
                                                                                        【甲】黔之驴
      黔无驴,有好事者船载以入。至则无可用,放之山下。虎见之,庞然大物也,以为神。蔽林间窥之,稍出近之,慭慭然,莫相知。
      他日,驴一鸣,虎大骇,远遁;以为且噬己也,甚恐。然往来视之,觉无异能者。益习其声,又近出前后,终不敢搏。稍近益狎,荡倚冲冒,驴不胜怒,蹄之。虎因喜,计之曰:“技止此耳!”因跳踉大,断其喉,尽其肉,乃去。
                                                                                        【乙】说 虎
     虎之力于人不啻(chì )①倍也。虎利其爪牙,而人无之,又倍其力②焉,别人之食于虎也,无怪矣。然虎之食人不恒见,而虎之皮人常寝处之,何哉?虎用力,人用智;虎自用其爪牙,而人用物。故力之用一③,而智之用百;爪牙之用各一,而物之用百;以一敌百,虽猛必不胜。故人之为虎食者,有智与物而不能用者也。是故天下之用力而不用智者,与自用而不用人者,皆虎之类也。其为人获而寝处其皮也,何足怪哉?
      注释:①啻(chì )只,仅。②又倍其力:它的力量又加倍了。③力之用一:力量的功用只有一点。

同类题5

任务型阅读

    Are These the Best Years of Your Life?

    The ups and downs of life may seem to have no predictable plan. But scientists now know there are very clear life patterns that almost all people share. Even if you have passed some of your best years, you still have other good years to come.____

    When are you smartest? From 18 to 25, according to I. Q. scores; but you are wiser and more experienced with increasing age. You're sharpest in your 20's; around 30, mental abilities begin to decline, particularly your ability to do maths.____ Your vocabulary at age 45, for example, is three times as great as when you graduated from college. At 60, your brain possesses almost four times as much information as it did at age 21.

    ____You have the best physical sense of yourself from 15 to 24, when you feel energetic all the time. The best professional sense seems from 40 to 49. Before age 24, we believe that our happiest years are yet to come. Over 30, we believe that they're behind us. A National Health Survey agrees: After age 30, we “become more realistic and do not view happiness as a goal in itself. If we keep our health, achieve professional and emotional goals, then happiness, we feel, will follow.”

    ____Generally between 30 to 39, but the peak(顶峰)varies with different professions. Mozart wrote a symphony by age eight, and Mendelssohn composed his best-known work, A Midsummer Night's dream, at 17, but most of the great music was written by men between 33 and 39. Though the peak in most fields comes early—most Nobel Prize winners did their top research in their late 20's and 30's, creative people continue to produce quality work throughout their lives.____

A. When are you happiest?

B. When are you most creative?

C. But your ability to complete other tasks climbs.

D. The above gives you an accurate figure.

E. Certain good years seem to come later in life.

F. For people who are creative, there is no upper age limit.

G. The human life journey cannot be charted by a clear life pattern.