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1取某植物的胚芽鞘和幼根,切除胚芽鞘尖端和幼根根尖的尖端(即切除根冠和分生区),然后将胚芽鞘(近尖端向上)和幼根(近尖端向上)直立放置,分别在两者切面的左侧放置含有生长素的琼脂块(生长素浓度为促进胚芽鞘生长的最适浓度),培养在黑暗条件下,幼根和胚芽鞘弯曲生长且方向相反,关于这一现象的说法,合理的是( )
A.胚芽鞘向左弯曲生长,生长素在胚芽鞘中是极性运输
B.胚芽鞘向右弯曲生长,生长素在胚芽鞘中是极性运输
C.幼根向左弯曲生长,生长素在胚芽鞘中是非极性运输
D.幼根向右弯曲生长,生长素在胚芽鞘中是非极性运输
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2一个基因型为AaBb(两对基因独立遗传)的精原细胞减数分裂可产生的配子种类是( )
A.四种
B.三种
C.二种
D.一种
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3某蛋白质由m条肽链、n个氨基酸组成。该蛋白质至少有氧原子的个数是( )
A.n-m
B.n-2m
C.n+m
D.n+2m
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4下列各组细胞结构中都可以发生碱基互补配对行为的是( )①细胞核 ②线粒体 ③叶绿体 ④中心体 ⑤高尔基体 ⑥核糖体
A.①②③④
B.②③⑤⑥
C.①④⑤⑥
D.①②③⑥
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5就一对联会的同源染色体而言,其着丝点数、染色单体数和多核苷酸链数分别是( )
A.2、4和4
B.2、8和4
C.4、4和4
D.2、4和8
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6有关动物细胞有丝分裂的叙述,正确的是( )
A.细胞板在细胞有丝分裂末期形成
B.同源染色体配对通常发生在分裂前期
C.在分裂末期,细胞膜内陷形成两个子细胞
D.在分裂中期,两个中心粒复制形成两组中心粒
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7甲、乙、丙是同一物种的三个种群,其年龄组成见下表。三个种群年龄结构的类型为( )<table style="BORDER-BOTTOM: medium none; BORDER-LEFT: medium none; MARGIN: auto 6.75pt; BORDER-COLLAPSE: collapse; BORDER-TOP: medium none; BORDER-RIGHT: medium none; mso-table-layout-alt: fixed; mso-border-alt: solid windowtext .5pt; mso-padding-alt: 0cm 5.4pt 0cm 5.4pt; mso-border-insideh: .5pt solid windowtext; mso-border-insidev: .5pt solid windowtext; mso-table-lspace: 9.0pt; mso-table-rspace: 9.0pt; mso-table-anchor-vertical: paragraph; mso-table-anchor-horizontal: margin; mso-table-left: center; mso-table-top: .1pt" border="1" cellspacing="0" cellpadding="0" align="left" _dj="MsoNormalTable"><tbody><tr style="HEIGHT: 15pt; mso-yfti-irow: 0; mso-yfti-firstrow: yes"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 86.9pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15pt; BORDER-TOP: windowtext 1pt solid; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt" rowspan="2" width="116">年龄期</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 260.85pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15pt; BORDER-TOP: windowtext 1pt solid; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt" width="348" colspan="3">个体数</td></tr><tr style="HEIGHT: 7pt; mso-yfti-irow: 1"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 86.9pt; PADDING-RIGHT: 5.4pt; HEIGHT: 7pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">甲</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 86.95pt; PADDING-RIGHT: 5.4pt; HEIGHT: 7pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">乙</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 87pt; PADDING-RIGHT: 5.4pt; HEIGHT: 7pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">丙</td></tr><tr style="HEIGHT: 15pt; mso-yfti-irow: 2"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 86.9pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">幼年期</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 86.9pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">600</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 86.95pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">400</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 87pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">200</td></tr><tr style="HEIGHT: 15.4pt; mso-yfti-irow: 3"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 86.9pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15.4pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">成年期</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 86.9pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15.4pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">400</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 86.95pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15.4pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">400</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 87pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15.4pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">400</td></tr><tr style="HEIGHT: 15pt; mso-yfti-irow: 4; mso-yfti-lastrow: yes"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 86.9pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">老年期</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 86.9pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">200</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 86.95pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">400</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: #000000; PADDING-BOTTOM: 0cm; BACKGROUND-COLOR: transparent; PADDING-LEFT: 5.4pt; WIDTH: 87pt; PADDING-RIGHT: 5.4pt; HEIGHT: 15pt; BORDER-TOP: #000000; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-left-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="116">600</td></tr></tbody></table>
A.甲是增长型,乙是稳定型,丙是衰退型
B.甲是稳定型,乙是增长型,丙是衰退型
C.甲是增长型,乙是增长型,丙是衰退型
D.甲、乙、丙三个种群都是稳定型
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8某对表现型正常的夫妇生出了一个红绿色盲的儿子和一个表现型正常的女儿,该女儿与一个表现型正常的男子结婚,生出一个红绿色盲基因携带者的概率是( )
A.1/2
B.1/4
C.1/6
D.1/8
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9将硝化细菌体内的核酸彻底水解后可以得到( )
A.C、H、O、N、P等元素
B.5种含氮碱基
C.4种核苷酸
D.8种核苷酸
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10人体肝细胞内CO2分压和K+浓度高于细胞外,而O2分压和Na+浓度低于细胞外,上述四种物质中通过主动运输进入该细胞的是( )
A.CO2
B.O2
C.Na+
D.K+
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