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1关于测交实验意义的说法,正确的是( )
A.通过测交可以获得优良性状的新品种
B.通过测交可以测定被测个体的遗传因子组合
C.通过测交得到的后代都能稳定遗传
D.通过测交得到的后代的性状表现相同
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2已知玉米某两对基因按照自由组合规律遗传,现有子代基因型及比值如下:则双亲的基因型是( )表 1 <table style="BORDER-BOTTOM: medium none; BORDER-LEFT: medium none; BORDER-COLLAPSE: collapse; BORDER-TOP: medium none; BORDER-RIGHT: medium none; 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" border="1" cellspacing="0" cellpadding="0" _dj="MsoNormalTable"><tbody><tr style="HEIGHT: 16.85pt; mso-yfti-irow: 0; mso-yfti-firstrow: yes"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 51.95pt; PADDING-RIGHT: 5.4pt; HEIGHT: 16.85pt; BORDER-TOP: windowtext 1pt solid; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt" width="69">基因型</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 51.95pt; PADDING-RIGHT: 5.4pt; HEIGHT: 16.85pt; 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="69">DDSS</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 51.95pt; PADDING-RIGHT: 5.4pt; HEIGHT: 16.85pt; 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="69">DDss</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 52pt; PADDING-RIGHT: 5.4pt; HEIGHT: 16.85pt; 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="69">DdSS</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 52pt; PADDING-RIGHT: 5.4pt; HEIGHT: 16.85pt; 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="69">Ddss</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 52pt; PADDING-RIGHT: 5.4pt; HEIGHT: 16.85pt; 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="69">DDSs</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 52pt; PADDING-RIGHT: 5.4pt; HEIGHT: 16.85pt; 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="69">DdSs</td></tr><tr style="HEIGHT: 17.7pt; mso-yfti-irow: 1; mso-yfti-lastrow: yes"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 51.95pt; PADDING-RIGHT: 5.4pt; HEIGHT: 17.7pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-alt: solid windowtext .5pt; mso-border-top-alt: solid windowtext .5pt" width="69">比例</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 51.95pt; PADDING-RIGHT: 5.4pt; HEIGHT: 17.7pt; BORDER-TOP: medium none; 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="69">1</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 51.95pt; PADDING-RIGHT: 5.4pt; HEIGHT: 17.7pt; BORDER-TOP: medium none; 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="69">1</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 52pt; PADDING-RIGHT: 5.4pt; HEIGHT: 17.7pt; BORDER-TOP: medium none; 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="69">1</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 52pt; PADDING-RIGHT: 5.4pt; HEIGHT: 17.7pt; BORDER-TOP: medium none; 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="69">1</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 52pt; PADDING-RIGHT: 5.4pt; HEIGHT: 17.7pt; BORDER-TOP: medium none; 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="69">2</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 5.4pt; WIDTH: 52pt; PADDING-RIGHT: 5.4pt; HEIGHT: 17.7pt; BORDER-TOP: medium none; 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="69">2</td></tr></tbody></table>
A.DDSS×DDSs
B.DdSs×DdSs
C.DdSs×DDSs
D.DdSS×DdSs
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3与有丝分裂相比较,减数分裂所特有的染色体行为是( )
A.DNA分子的复制
B.着丝点的分裂
C.染色质形成染色体
D.出现四分体
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4有5个卵原细胞,经过两次连续的细胞分裂,形成结果是( )
A.20个卵细胞
B.10个卵细胞和10个极体
C.5个卵细胞和5个极体
D.5个卵细胞和15个极体
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5下列关于染色体、DNA、基因、脱氧核苷酸之间关系的叙述错误的是( )
A.一条染色体含有很多个DNA分子
B.一个DNA分子含有多个基因
C.一个基因含有多个脱氧核苷酸
D.基因在染色体上呈线性排列
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