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问题 单项选择题 A1/A2型题

关于生长曲线的叙述，哪项不正确（）

A.生长曲线是以时间为横坐标，培养物中的细菌数的对数为纵坐标

B.生长曲线可分为4期，即迟缓期，对数期、稳定期及衰亡期

C.生长曲线对研究工作及生产实践有指导意义

D.典型生长曲线可根据细菌在体内的生长特点而绘制

E.细菌在体内的生长曲线与其在培养基中的生长曲线有差异

答案

参考答案：D

解析：将一定量的细菌接种于适宜的液体培养基中进行培养，间隔不同时间取样检查细菌数，观察其生长规律。以生长时间为横坐标，培养物中菌数的对数为纵坐标，可得出一条曲线，称为细菌的生长曲线。

单项选择题

尽管治疗哮喘病的手段有所提高，但是在过去10年里，哮喘病的死亡率比以前提高了1倍。死亡率的升高有两个可能的原因：其—，在过去10年里，对哮喘病死亡的记录与以前相对变得更加广泛和准确；其二，城市污染有所增加。然而，即使在很少或者没有污染，且具有长期综合医疗记录的城市里，哮喘病的死亡率也呈急剧增加之势，因此，一定可以得出相反的结论：死亡率的升高起因于哮喘病患者为减轻症状而使用支气管吸人器。
下面每一项，如果正确，除了哪一项之外都可对上述论证构成支持( )

A．城市人口在过去10年中增加了1倍
B．10年以前，作为治疗哮喘病的支气管吸入器还没出现
C．有证据表明，支气管吸入器使肺对空中传播的花粉更易发生过敏反应
D．只有暂时地解除哮喘病的症状，吸入器使患者错过了其他更有益治疗的机会
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单项选择题

(Ⅰ)

In the dining room of my grandfather’ s house stood his heavy clock. Meals in the dining room were a (21) for our four generations to become one. My grandfather’ s clock always stood like a trusted old family friend, (22) us playing jokes and tellingstories, which was already a (23) of our life.

When I was a child, the old clock interested me. I watched and listened to it during (24) I was surprised how at (25) times of the day, the clock would strike three times, six times or more, with a wonderful great (26) that echoed throughout the house. The clock chimed year after year, a part of my (27) , a part of my heart.

Even more (28) to me was my grandfather’s special action each day. He meticulously (29) the clock with a special key each day. The key was magic to me. It (30) our family’ s magnificent clock ticking and striking all year round.

25（）

A. busy

B. urgent

C. happy

D. different
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