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【简答题】
（4分）玉米是我市重要的粮食作物之一，玉米幼苗有的是绿色的正常苗，有的是叶片发白的白化苗。白化苗由于缺乏叶绿素而不能进行光合作用，会过早死亡。请分析回答下列问题： （1）玉米被称为“黄金作物”，富含淀粉、脂肪、胡萝卜等营养物质，这些营养物质储存于玉米种子的___________中。 （2）玉米的白化不利变异，引起这种变异的原因是____________________。 （3）玉米能产生叶绿素是由于它拥有显性基因B，而是隐性基因b则令玉米丧失产生叶绿素的能力。则白化苗的基因组成是__________。 （4）科研人员将两株玉米杂交后，再收集种子种植。在935粒成功萌芽的种子中，有705粒发育成绿色幼苗，余下的幼苗为白化苗。请写出这些绿色幼苗的基因组成______________。
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【简答题】In the past, a university could expel regular students if they got married during their studies. This ban has compelled students who were contemplating marriage or got pregnant to make painful choices...
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A.
make… do
B.
makes …does
C.
makes …do
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A.
Some mothers try to influence their unborn children by studying art and other subjects during their pregnancy.
B.
It is utterly impossible for us to learn anything about prenatal development.
C.
The blood vessels of mother and child do not join directly.
D.
There is no connection between mother's nervous systems and her unborn child's.
【单选题】John, a friend of mine, _____ got married only last week, spent ＄3000 more than he _____. [ ]
A.
whom; will plan
B.
who; has planned
C.
whom; would plan
D.
who; had planned
【单选题】Sir Elton John, the famous singer, got married to his long-time partner in a civil marriage ceremony held in Windsor Guildhall on 21st December 2005. Nothing special about that, you might say, until y...
A.
marriages between people of the opposite sex
B.
marriages of the elderly people
C.
marriages between people of the same sex
D.
marriages across the borders
【单选题】Look！My mother _____ cakes. She often _______ cakes for us. [ ]
A.
makes, makes
B.
making , make
C.
is making, makes
D.
is making , is making
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