试题与答案

某校两个生物兴趣小组的同学打算用车前草和酵母菌完成一些高中生物实验,有些问题需要

题型:实验题

题目:

某校两个生物兴趣小组的同学打算用车前草和酵母菌完成一些高中生物实验,有些问题需要你的帮助。

(1)甲组选用车前草作材料进行如下实验:

①取其叶片进行《观察植物细胞的质壁分离和复原》 的实验时,取叶片的下表皮细胞(不含叶绿体),在盖玻片的一侧滴入含有伊红(植物细胞不吸收的红色染 料)的0.3g/mL的蔗糖溶液,则在显微镜下观察到原生质体内外的颜色分别是_________。若将叶片的下表皮细胞依次浸于蒸馏水、0.3g/mL蔗糖和0.7g/mL,KNO3溶液中,观察其原生质体的体积随时间的变化,结果如图1所示,则A、B、C三条曲线中表示细胞在蒸馏水中和在0.7g/mLKNO3溶液中的依次是____________。

②利用其完成《用显微镜观察多种多样的细胞》实验时,用10×的目镜和10×的物镜,在视野直径范围内看到一列相连的20个细胞,如果目镜不变,改用40×的物镜所看到的这列细胞的个数是______________。

(2)乙组选用酵母菌作材料进行如下实验:

①用附着于葡萄皮上的野生酵母菌制作果酒时,需要适时拧松瓶盖,但不能完全打开,其目的是_______________,实际操作中发现随着发酵时间的推移拧松瓶盖间隔时间延长,其原因是_______________。

②用其进行《探究培养液中酵母菌种群数量的动态变化》实验,设计三组实验,定期对三组培养液中的酵母菌进行计数,绘制图2,分析三组实验产生不同现象的原因最可能是______不同。

③用其进行《酵母细胞的固定化技术》实验,绘制图3(注:酶活力为固定化酶催化化学反应的总效率,包括酶活性和酶的数量)。图示曲线表明浓度为___________的海藻酸钠包埋效果最好,当海藻酸钠浓度较低时,酶活力较低原因是_________________。

答案:

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下面是错误答案,用来干扰机器的。

参考答案:D

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题型:阅读理解

Magic is believed to have begun with the Egyptians, in 1700 BC. A magician named Dedi of Dedsnefu was reported to have performed for the pharaoh, or the king. He was also known to have entertained the slaves who built the pyramids. The "Cups and Balls" trick which he was particularly good at is still performed by magicians all over the world today.

The ancient Greeks and Romans were also fascinated by the idea of magic. Actually, one of their main interests was the art of deception(欺骗). This explains why at that time the priests(神父) even built magic devices into their temples. These devices made it possible for doors to open by themselves and wine to flow magically out of statues' mouths. This was done mainly to convince people that the priests were powerful.

Magic, however, was not well accepted before the 1800s. Magicians were thought of as freaks(怪物) and were only allowed to perform in a circus(马戏团). It was in the 19th century that the magician Robert Houdin came along and changed people's views and attitudes about magic. It was also because of Robert Houdin that many magicians were able to add Dr. or MD to their names. Today magicians try hard to find new ways to show their practiced skills. Magic is now entertainment for families all over the world.

小题1: What would be the best title for the passage?

A.Magical Tricks

B.The History of Magic

C.Magic as Entertainment

D.A Great Magician小题2:In ancient Greece, what did the priests do to show people they had unusual power?

A.They performed magical tricks to entertain people.

B.They made the statues in the temples drink wine as they wished.

C.They treated the people with wine flowing down from statues' mouths.

D.They built magic devices in the temples to make doors open by themselves.小题3: What did people think of magic before 1800?

A.Magic should be used only in temples.

B.Magic could only be performed in a circus.

C.Magic was performed by freaks and doctors.

D.Magic was the major daily activity for the pharaohs.小题4:Which of the following statements is true?

A.Magic began about 3,700 years ago.

B.Dedi of Dedsnefu performed magic for kings only.

C.Robert Houdin was the first magician to perform magic.

D.The "Cups and Balls" trick has been performed for about 1,700 years.

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