七年级1班生物兴趣小组的几位同学在做“馒头在口腔中的变化”的探究实验时,采用了不

题型:探究题

问题:

七年级1班生物兴趣小组的几位同学在做“馒头在口腔中的变化”的探究实验时,采用了不同的处理方法,具体如下:

1号试管:加入馒头碎屑和2毫升唾液,并充分搅拌;

2号试管:加入馒头碎屑和2毫升清水,并充分搅拌;

3号试管:加入馒头块和2毫升唾液,但不搅拌。

将3支试管都放入37℃的温水中保温10分钟,取出冷却后分别加入2滴碘液,摇匀后观察试管中馒头的颜色变化。请问:

(1)1号试管馒头碎屑没有变色,原因是馒头中的__________在________酶的作用下变成了麦芽糖。

(2)2号试管馒头碎屑变色的原因是                      

(3)3号试管馒头块变色的原因是_________                 _。

(4)该实验成功可以说明淀粉在消化道的_________开始被消化。

考点:食物中的营养物质
题型:探究题

根据短文内容,从短文后的七个选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Sometimes willpower is a lot like the television remote control hard to find just when you want it most. 小题1:  But there are ways to increase your willpower.

Don’t try to change your economic situation, win a promotion and lose weight all on the same morning. Set one clear, specific goal and make a realistic plan to achieve it.Extra willpower sometimes requires extra energy, so don’t spread yourself too thin. 小题2:  

Whatever your goal is, don’t expect to achieve it overnight. 小题3:  If you are trying to kick a coffee habit, start by replacing your morning cup of coffee with a glass of water, instead of promising never to drink coffee again. Congratulate yourself on the small achievements. These successes help your willpower grow.

 小题4:  Ask friends, family or colleagues for assistance and tell them exactly how they can help. If your credit card bills have risen, for instance, let friends know that you are cutting back on expenses. Suggest having a common dinner instead of meeting at an expensive restaurant. Find a support group or organization related to your goal and attend their meetings. You can get valuable advice, understanding and information.

If possible, change your environment to encourage positive behavior.Want to get in shape? Keep an extra set of workout clothes in your office as a reminder to stop by the gym on the way home.Quitting smoking?   小题5:  

A.Real success takes time.

B.Focus on one goal at a time.

C.Change your environment to change your life.

D.Improve your willpower by a support network.E. Changing your behavior requires more than willpower.

F. Avoid bars or restaurants where you might be attracted to light up.

G. Breaking a bad habit or forming a new and healthy one can be difficult.

题型:探究题

当声波通过介质时造成的波幅和强度的减弱称为()

A.吸收

B.衰减系数

C.阻抗

D.衰减

E.发散

题型:探究题

下列对加粗词语的意义和用法,判断正确的一项是[ ]

所以兴怀,其致一也

所以学者不可以不深思而慎取之也

而余亦悔随之而不得极夫游之乐也

尽吾志也而不能至者,可以无悔矣,孰能讥之乎

A.两个“所以”相同,两个“其”也相同

B.两个“所以”不同,两个“其”也不同

C.两个“所以”不同,两个“其”相同

D.两个“所以”相同,两个“其”不同

题型:探究题

缺铁性贫血的最常见病因是()

A.慢性胃炎

B.慢性肝病

C.慢性感染

D.慢性溶血

E.慢性失血

题型:探究题

上紧气缸盖螺栓时,应采用从()的交替上紧方法。

A.从两边向中间

B.从左边到右边

C.从右边向左边

D.从中间向两边

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