某双链DNA分子共有含氮碱基1400个，其中一条单链上(A+T):(C+G)=2:5。则该DNA分子连续复制两次共需游离的胸腺嘧啶脱氧核苷酸的数目是（    ）

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• 1人类的红绿色盲基因位于X染色体上，父母表现型正常，生下3胞胎孩子。其中只有一个患色盲，有两个孩子为同卵双胞胎。3个孩子的性别不可能是（    ）

  A.2女1男

  B.全是男孩子

  C.全是女孩或2男1女

  D.全是男孩或2女1男

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• 2下列需要进行遗传咨询的是（    ）

  A.亲属中生过先天性畸形孩子的待婚青年

  B.患过艾滋病的妇女

  C.母亲的血型为O型血，咨询其子女的血型

  D.得过乙型脑炎的夫妇

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• 3下列六种遗传病中属于性染色体病的是（    ）①苯丙酮尿症            ②21三体综合征            ③性腺发育不良④青少年型糖尿病        ⑤抗维生素D佝偻病         ⑥猫叫综合症

  A.③

  B.③⑤

  C.①③④⑤

  D.②③⑥

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• 4若“M → N ”表示由条件M一定能推得N，则这种关系可表示为（    ）

  A.M表示遵循基因分离定律，N表示遵循自由组合定律

  B.M表示基因频率的改变，N表示生物的进化

  C.M表示基因突变，N表示性状的改变

  D.M表示某单倍体植株，N表示用秋水仙素处理得到纯合体

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• 5假定某致病基因a位于X染色体上，且隐性致死（使受精卵、胚胎致死）。一男子与一女性携带者结婚，理论上分析，这对夫妇所生的小孩性别比例（女孩：男孩）是（    ）

  A.1 ：1

  B.1 ：0

  C.3 ：1

  D.2：1

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• 6在一个DNA分子中，腺嘌呤与胸腺嘧啶之和占全部碱基数目的54%，其中一条链中鸟嘌呤、胸腺嘧啶分别占该链碱基总数的22%和28%，则一般来说由该链转录的信使RNA中鸟嘌呤占碱基总数的（    ）

  A.24%

  B.22%

  C.26%

  D.23%

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• 7右边表格表示某草原生态系的食物网情况（√表 示其左侧竖栏所示生物以上面横栏中所示生物为食），以下分析正确的是（    ） <table style="BORDER-BOTTOM: medium none; BORDER-LEFT: medium none; BORDER-COLLAPSE: collapse; MARGIN-LEFT: 6.75pt; BORDER-TOP: medium none; MARGIN-RIGHT: 6.75pt; BORDER-RIGHT: medium none" border="1" cellspacing="0" cellpadding="0" align="right" _dj="MsoNormalTable"><tbody><tr style="HEIGHT: 19.15pt"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.75pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: windowtext 1pt solid; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: 1pt solid; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">草</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: 1pt solid; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">a</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: 1pt solid; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">b</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: 1pt solid; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">c</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: 1pt solid; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">d</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: 1pt solid; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">e</td></tr><tr style="HEIGHT: 19.15pt"><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: 1pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.75pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">a</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">√</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td></tr><tr style="HEIGHT: 19.15pt"><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: 1pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.75pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">b</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">√</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td></tr><tr style="HEIGHT: 19.15pt"><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: 1pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.75pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">c</td><td style="BORDER-BOTTOM: 1pt solid; 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BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td></tr><tr style="HEIGHT: 19.15pt"><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: 1pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.75pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">d</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">√</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td></tr><tr style="HEIGHT: 19.15pt"><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: 1pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.75pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">e</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">√</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33">√</td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td><td style="BORDER-BOTTOM: 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 24.8pt; PADDING-RIGHT: 5.4pt; HEIGHT: 19.15pt; BORDER-TOP: medium none; BORDER-RIGHT: 1pt solid; PADDING-TOP: 0cm" valign="top" width="33"> </td></tr></tbody></table>

  A.此食物网有4条食物链

  B.如果人类大量捕杀c会使d的数量减少

  C.次级消费者有b、d、e

  D.如果能量传递效率都按10%计算，并且草传递给b和c的能量相等，那么a的能量与d的能量相等

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• 82008年9月，有北美“吸血鬼”之称的悬铃木方翅网蝽惊现成都，它用针状的嘴专刺吸梧桐叶里的汁液，导致成都70%梧桐树叶片枯黄脱落，树木提前进入“冬季”。下列说法正确的是（    ）①悬铃木方翅网蝽与法国梧桐之间的关系属于寄生      ②外来物种的入侵是破坏我国生物多样性的主要原因    ③悬铃木方翅网蝽刺吸梧桐叶汁液，可以导致叶片光合作用减弱，影响生长    ④生物多样性包括三个层次：基因多样性、遗传多样性、物种多样性  ⑤悬铃木方翅网蝽的个体发育属于变态发育    ⑥由于受自身密度影响，悬铃木方翅网蝽种群最终呈“S”型曲线增长

  A.①③⑤⑥

  B.②③④⑤

  C.③④⑤⑥

  D.①②③⑤

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• 9下列有关生态系统能量流动的叙述中，正确的是（    ）

  A.一种蜣螂专以象粪为食，则该种蜣螂最多能获取大象所同化能量的20%

  B.当狼捕食兔子并同化为自身的有机物时，能量就从第一营养级流入第二营养级

  C.生产者通过光合作用合成有机物，能量就从非生物环境流入生物群落

  D.生态系统的能量是伴随物质而循环利用的

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• 10下列有关干旱区域的生物与环境之间关系的叙述，正确的是（    ）

  A.干旱区域的生态系统食物链少，抵抗力稳定性强

  B.干旱区域的生态系统自动调节能力弱，恢复力稳定性强

  C.经干旱环境长期诱导，生物体往往发生耐旱突变

  D.种群密度是限制干旱区域生物种群数量增长的关键生态因素

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