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3.某植物的光合作用和细胞呼吸最适温度分别为25℃和30℃,下图为该植物处于25℃环境中光合作用强度随光照强度变化的坐标图。下列叙述正确的是

A.a点时叶肉细胞的生理活动只受温度的影响

B.b点时植物才开始进行光合作用

C.若将温度从25℃提高到30℃时,a、d点均上移

D.c点时该植物的O2产生量为N1

答案:C(据图分析,a点时叶肉细胞进行呼吸作用,但不进行光合作用,细胞呼吸守多种因素的影响。B点时植物光合作用产生的氧气量等于呼吸作用吸收的氧气量;c点时该植物的O2产生量为N1+ N2.若将温度从25℃提高到30℃时,光合作用减弱,产生的氧气的较少,但呼吸作用增强,吸收的氧气量增加。)

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2.下列关于细胞内ATP的叙述中,正确的是

A.适宜光照下,叶绿体和线粒体合成的ATP都需要O2

B.叶绿体和线粒体都有ATP合成酶

C.人体细胞内储存有大量ATP,以保证生命活动所需

D.光照下,植物叶肉细胞的叶绿体基质中能够产生ATP

答案:B(细胞中ATP 的形成不一定需要氧气,叶绿体和线粒体都有ATP,故其都具合成酶,细胞内储存的ATP数量较少,但转化很快;光照下,植物叶肉细胞的叶绿体中的类囊体中能够产生ATP,叶绿体基质中消耗ATP。)

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1.下列有关真核细胞分裂的叙述,正确的是

A.在减数第二次分裂前期不含染色单体

B.在细胞分裂间期,DNA复制,染色体数目加倍

C.在减数第一次分裂的前期和后期均可能发生基因重组

D.处于有丝分裂后期的果蝇体细胞有两个染色体组

答案:C(细胞分裂间期,DNA虽然发生复制,但着丝点没有分开,故染色体数目不变;果蝇是二倍体生物,其体细胞中有两个染色体组,细胞有丝分裂后期有四个染色体组;在减数第一次分裂的前期同源染色体上的非姐妹染色单体之间可发生互换,后期非同源染色体自由组合均可能发生基因重组;减数第二次分裂前期每条染色体上含有染色单体。)

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19.The movie star was injured in a car accident before his performance,     made everyone at

present worried.

  A.who           B.that          C.what          D.which

  答案  D

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18.A terrible earthquake happened in that district at the end of 2004,     many people all over the world visited there.

  A.what          B.which         C.when          D.where

  答案  C

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17.It was in the stone house     was built as a school by local villagers     the boy

  finished his primary school.

  A.which;that       B.that;where       C.which;which      D.that;which

  答案  A

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16.It was on October 15     the Communist Party 17th Congress began,       was the biggest

political meeting in five years.

A.which;that       B.what;which       C.which;who       D.that;which

答案  D

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15.-How much do you have in your pocket?

  -150 yuan,all of    came from my grandma.

  A.which          B.them          C.it           D.that

  答案  A

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14.I wonder if it was in the bookstore      I bought some books      I lost the keys.

  A.that;that        B.where;where      C.where;that       D.that;where

  答案  C

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13.Finally they arrived at a place,        sold cigarettes and other small articles.

  A.where          B.which         C.in which        D.what

  答案  B

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