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下列实验数据合理的是()

A . 用托盘天平称取15.6gNaCl固体 B . 农作物一般适宜在pH为12—14的土壤中生长 C . 用普通温度计测得某液体温度为25.62℃ D . 用10mL量筒量取6.65mL某溶液
相同重量的大米和花生种子中,含能量的情况是(  )


A . 相等 B . 大米种子能量多  C . 花生种子能量多   D . 无法判断
横线里最大可以填几?

×41<247        29×<209       85×<530

53568≈50万    25263≈30万     34248≈34万.

酒精浓度过高会抑制酵母菌的生长繁殖,影响酒精产量。为此,研究人员将酒精耐受基因转入野生型酵母菌中,经筛选得到了耐高浓度酒精的酵母菌。过程如图甲所示,请据图回答下列问题:

图片_x0020_337409987

  1. (1) 通过筛选得到耐高浓度酒精酵母菌的技术是。②、③过程需要重复几次,目的是。某同学尝试过程③的操作,其中一个平板经培养后的菌落分布如图乙所示。该同学的接种方法是
  2. (2) 为证明分离纯化得到的酵母菌能提高酒精产量,可将等量的和耐高浓度酒精的酵母菌分别接种于含等量葡萄糖的A、B两组发酵装置中,在℃条件下(填“密闭”或“充气”)培养。一段时间后取样,用检测,若实验结果为,则说明耐高浓度酒精的酵母菌能提高酒精产量。
观察并制作洋葱鳞片叶表皮细胞临时装片时,用到的材料和用具有(  )

①镊子②生理盐水③稀碘液④清水⑤消毒牙签⑥刀片⑦纱布

A . ①②③⑤⑦ B . ①②⑥⑦ C . ①②③④⑤⑥⑦ D . ①③④⑥⑦
母亲节,轩轩给妈妈准备下午茶,如下图饮料和蛋糕各选1种,一共有种不同的搭配。

把65.19的小数点移动到最高位的左边,它就缩小到原来的,变成

选出不同类的单词(   )
A . often B . angry C . sometime D . never
阅读下面短文,从短文后各题所给的A、B、C 和 D四个选项中,选出可以填入空白处的最佳选项。

    A teacher was giving a lesson to her students on stress management (压力管理). As she raised a glass of water, everyone in the class 1 they would be asked the "half-empty or half-full" question.

    2, that was not the case. With a smile on her face, she asked the students, "How 3 do you think this glass of water weighs?"

    Answers called out ranged from eighty to twenty ounces (盎司).

    She quieted the students down and then replied, "The absolute weight doesn't 4. But it 5 on how long you hold it. If I hold it for a minute, it is OK. If I hold it for an hour, I will have an ache in my right 6 . If I hold it for a day, my arm will feel numb(麻木). In each case, the 7 of the glass of water doesn't change, but the 8 I hold it, the heavier it becomes. Why?"

    Lost in 9, all the students kept silent and listened to the teacher carefully.

    "Our 10 and worries in life are like that glass of water. If we 11 our burdens(负担) all the time, sooner or later, we will feel very tired, even unable to 12.

    All you have to do is put all your burdens down, as 13 in the evening as possible. Don't carry 14 through the evening into the night; by doing this, we can get 15 next morning and are 16 to move forward.

    More often than not, life gets terrible when we 17 too much. And the moment you 18your burdens, you'll find yourself feeling so much more 19.

    So rather than being upset and feeling 20 for yourself, start doing something about it. After all, life is too short to abandon yourself to anything that is not making you happy.

(1)
A . wondered B . agreed C . expected D . argued
(2)
A . However B . Meanwhile C . Anyhow D . Therefore
(3)
A . full B . little C . heavy D . much
(4)
A . exist B . decrease C . matter D . raise
(5)
A . holds B . calls C . takes D . depends
(6)
A . finger B . foot C . arm D . leg
(7)
A . shape B . function C . size D . weight
(8)
A . better B . longer C . deeper D . further
(9)
A . thought B . idea C . plan D . class
(10)
A . doubts B . joys C . stresses D . surprises
(11)
A . carry B . cover C . hide D . show
(12)
A . get up B . work out C . move on D . come up
(13)
A . late B . early C . soon D . fast
(14)
A . this B . that C . them D . it
(15)
A . refreshed B . amazed C . hopeless D . depressed
(16)
A . able B . anxious C . passive D . eager
(17)
A . fear B . think C . rest D . get
(18)
A . catch up with B . let go of C . put up with D . take care of
(19)
A . relaxed B . stressful C . worried D . successful
(20)
A . sorry B . satisfied C . happy D . amazed
选择正确的读音

发 (shì  sì)    愧(cán   jiàn)      杀无辜(nàn   làn)

 责(cì   chì)   帝(hánɡ  huánɡ)   样(bǎn  bǎnɡ)

下列粒子结构示意图中,表示阴离子的是(   )
A . B . C . D .
2016年12月7日至8日,全国高校思想政治工作会议在北京召开。习.平总书记出席会议并发表重要讲话指出,要坚持不懈培育和弘扬社会主义核心价值观,引导广大师生做社会主义核心价值观的坚定信仰者、积极传播者、模范践行者。培育和弘扬社会主义核心价值观,广大师生应该(  )

①深刻理解社会主义核心价值观的本质内涵

②在学习和生活中自觉践行社会主义核心价值观

③主动推动社会主义核心价值观走向世界

④以社会主义核心价值观为文化创新的精神根基

A . ①② B . ①③ C . ②③ D . ③④
2018年4月2日,习.平主席在参加首都义务植树活动时强调,像对待生命一样对待生态环境,让祖国大地不断绿起来美起来。“像对待生命一样对待生态环境”的依据是(    )

①保护环境、节约资源是我国的基本国策

②践行绿色发展,建设美丽中国

③保护生态环境是当前的中心工作

④我国生态环境已经恶化,无法改善

A . ①② B . ②③ C . ②④ D . ①④
遗传学上将常染色体上的基因只在一种性别中表现的现象称为限性遗传,如图所示的单基因遗传病存在限性遗传现象,其中I1和I2为纯合子。列分析正确的是(  )

A . 该病的遗传方式为常染色体显性遗传 B . 2、Ⅱ3、Ⅲ2的基因型相同 C . 4与正常男性婚配,所生儿子患病的几率是1/3 D . 若Ⅱ1为杂合子,则Ⅲ1的基因型与I1相同的概率为1/3
已知sin α=- ,α∈(π, π),cos β=- ,β∈( ,π),则cos(α-β)=.
在下面的横线上填上“>”、“<”或“=”。

钝角90°            689500680万

周角2个平角       15×600150×80

袁隆平院士被国内外尊称为“杂交水稻之父”,他所培育的高产水稻品种已在世界多地种植。下列观点正确的是(  )
A . 稻田中生物数量多,所以稻田是一个生态系统 B . 稻田要人工除草,说明该生态系统没有自动调节能力 C . “阳光→水稻→害虫→青蛙”构成一条完整的食物链 D . 杂交水稻的高产性状是可遗传的变异
方程 的根为(   )
A . B . C . D .
比一比,再组词。

以下化学用语正确的是(   )
A . 苯的最简式:C6H6 B . 甲醛的结构式: C . 乙烯的结构简式:CH2CH2 D . 乙醇的分子式:CH3CH2OH
教材章节知识点
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