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43.A.when      B. until      C.while      D.if

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42.A.cause      B.make      C.use       D.allow

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41.A.white      B.blue      C.green      D.yellow

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40.A.passing      B.getting     C.giving     D.dying

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39.A.alive      B.healthy     C.dead      D.ill

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38.A.way       B.method     C.habit      D.tradition

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37.A.feel      B.believe     C.wish      D.think

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Mom had a way with all things  41 . My sister and I always joked, “Mom could  42  a telephone pole grow leaves and bear fruit.”

Why can’t I? I thought. Still, I couldn’t bear to throw the dead plant away. Instead, I placed it into a dark corner of our bathroom. I didn’t even water it. I just left it there  43  I could deal with it.

My husband asked me if I was going to wear a white flower to church that Mother’s Day. “Yes,” I told him, “but I need a  44  gardenia.” I added silently.

Sunday morning I woke up early to get dressed and made for the  45 . Still  46 , I walked to the bathroom. Suddenly I was woken up by a pleasant scent (香味). I pushed the door open and stepped into the bathroom. That morning I knew I would be ready to wear a small white flower for Mom. In that dark corner,  47  as if it had a light of its own, bloomed a perfect white gardenia!

36.A.everything   B.nothing     C.anything    D.something

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35.(14分)甲、乙、丙三位同学均对酵母菌的生长情况进行了探究。甲、乙两同学先配制了含有酵母菌生长所必需的各种营养成分的培养液,调节到酵母菌生长的最适pH,各取

1mL于试管中,接种等量的酵母菌菌种,放在适宜的条件下培养一段时间,进行计数。

(1)甲同学直接取培养液,用血球计数板制成装片,在显微镜下进行计数,观察到的图像如右图所示。已知计数板方格总边长为1mm,涂抹厚度为0.1 mm。

①在从试管中吸出酵母菌培养液时,为了确保随机取样,必须          

②若计得每一小格中酵母菌平均为10个,则该1mL培养液中共含有酵母菌约      个。

(2)乙同学将500个红细胞与该1mL培养液混匀后制片观察,进行随机统计,结果如下:

 
视野1
视野2
视野3
视野4
红细胞数(个)
21
17
22
20
酵母菌数(个)
102
98
106
94

则:①该同学调查模拟了种群密度调查中的        (方法)原理。

②该1mL培养液中共含有酵母菌大约       个。

(3)丙同学欲探究pH对酵母菌生长的影响,他的实验如下,请补充完整。

①配制含酵母菌生长所必需的各种营养成分的培养液,各取2mL加入数支试管中;

                                  

                                  

                                  

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34.( 9分)在做土壤中分解尿素的细菌的分离与计数的实验时,甲同学筛选出的菌落与其他同学不同,并且他在设计实验时并没有设置对照。思考下列问题:

   (1) 你认为出现甲同学这种结果的原因可能是                 

                       (2分)。

(2) 要帮助甲同学排除可能影响实验结果的因素,需要设置对照实验,实验方案有两种:一种方案是可以由其他同学用与甲同学     进行实验,如果结果与甲同学一致,则证明甲同学    ,如果结果不同,则证明甲同学存在操作失误或     的配制有问题。另一种方案是将甲同学配制的培养基在不加   的情况下进行培养,作为空白对照,以证明培养基是否受到    

(3)在105稀释度下得出3个平板上菌落数的平均值是63,则每克样品中的菌落数为    

(4)怎样初步鉴定某中细菌能够分解尿素?

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