题干

如表是某学习小组的同学探究“胆汁对花生油的乳化作用”的实验方案,有关分析正确的是(   )

操作步骤

试管1

试管2

先加入的物质

2毫升花生油

2毫升花生油

后加入的物质

10滴新鲜的鱼的胆汁

①

摇匀,30秒后观察现象

a

B

A:在试管2中,后加入的物质①是10滴新鲜的鸡的胆汁

B:实验现象a是两种物质分层明显,实验现象b是形成乳状液

C:胆汁对花生油的乳化作用属于化学性消化

D:在以上探究实验中,试管1是对照组,试管2是实验组

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答案(点此获取答案解析)

D

同类题3

阅读下面文章,完成各题。

成功的秘诀

       ①古往今来,成功始终是一个绕不开的话题,采撷成功的花朵,是芸芸众生共同的追求。那么成功的秘诀是什么呢?有人认为,成功要有鸿鹄之志;有人认为,成功要得到命运的垂青……其实,自信是成功的第一秘诀。

       ②自信是对前途充满必胜的信念。坚信“有志者,事竟成”的项羽,做出了破釜沉舟的壮举,孤军突进,一举击溃秦军主力,创下“百二秦关终属楚”的军事神话。坚信“天生我材必有用”的李白,仕途失意后,用全部才情打造了一个浪漫瑰丽的诗歌世界,流芳百世,光耀千秋。坚信不走寻常路才有光明前途的李娜,义无反顾地踏上了职业化的道路,一路走来,先后在法网和澳网封后,彻底打破了欧美选手对四大满贯赛事的统治局面,成为亚洲网坛一姐。由此可见,必胜的信念能够为人插上飞向成功之巅的翅膀。

       ③自信是对目标执着的追求。水滴石穿,绳锯木断,当一个人执着于一个目标,并脚踏实地不懈奋斗,他一定会收获辉煌的成功,至少会书写一段无悔的人生。正如居里夫人曾对友人所说的那样,“我们必须要有恒心……无论代价有多大,这种事情必须做到”。为了改变新中国的贫油面貌,李四光风餐露宿,披荆斩棘,足踏千山,脚涉万水,风尘苦旅30载,相继发现大庆油田、胜利油田、华北油田等多处油田,并成功预见了今天正在开发的新疆大油田,成为共和国杰出的地质学家。为了解决亿万生命的吃饭问题,袁隆平废寝忘食、潜心钻研,以稻田为家园,视秧苗为亲人,白首不坠青云之志,浮华难动济世之心,为中国和世界粮食生产做出不可磨灭的贡献,被誉为“杂交水稻之父”。所以,若想成功就得坚韧执着,就要忠于自己的梦想。

       ④历史上无数成功的事例和经验证明了自信之于成功的重要,然而,盲目的自信是自负,必然导致失败。前秦苻坚,过于自信,刚愎自用,导致80万大军在淝水之战中惨败,他自己也身中流箭,仓皇逃回北方。骄傲自满,毫无自知之明,怎能不吞下失败的苦果?真正的自信,应当建立在对自己、对他人、对时势清醒认识的基础之上。

       ⑤青年朋友,愿你选定目标,坚定信念,锲而不舍地去奋斗,早日踏上成功之路。

(原文有改动)

同类题4

阅读理解

    On 20th July 1969, millions of people saw Neil Armstrong take his first steps in space on television. Armstrong got out of the spacecraft Apollo 11, touched the ground of the moon and said, “That's one small step for man, one giant leap for mankind.”

    A conspiracy(阴谋)theory has existed since the night of his lunar handing. Armstrong's achievements were considered amazing, but people wondered if it really happened. Many people believe that the scene on the moon wasn't real. Rumours spread throughout coffee shops, street comers, and newspapers, but it soon died down.

    But theories resurfaced in 2001 Suspicion began when an American television network aired a program called Conspiracy Theory: Did We Land on the Moon? The show argued that NASA did not have the money for such a voyage, and that the whole scene was probably filmed in a movie studio. Many critics say that there were no stars in the background during the lunar landing, so it must have been a fake. They also point out that the American flag that was posted was waving. How could that be if there is no wind on the moon?

    NASA(National Aeronautics and Space Administration)has denied these rumours many times. They explained that now photographers can capture the brightness of the astronauts with the dimness of the stars behind them. Also, they said that the flag was waving because the astronauts were pulling it back and forth trying to get it deeper into the rock. NASA also points out that the television program fails to mention that Armstrong and his team brought back 800 pounds of rock from the moon.

    Nell Armstrong is seen as a national icon in the US and his lunar landing is one of the most historic events in the country's history. But either way, this conspiracy theory still exists today.