题目

I had a very unusual experience on【小题1】星期天。At around ten   o'clock in the morning, I was walking down the street when a UFO landed in 【小题2】f_____ of me. You can imagine how【小题3】奇怪的it was! An alien got out and walked down the Center Street. I 【小题4】跟随it to see where it was going, and I was very surprised when it went into a souvenir shop. While it was looking at the souvenirs, the assistant called the 【小题5】p_______.(08东北四校联考)(22分)果蝇是研究遗传学的典型材料。请你分析提供的各种信息,回答下列问题:(1)果蝇属于                    倍体,其性别决定方式为                     。(2)果蝇的相对性状有多对,如:残翅型和长翅型,刚毛型和截毛型。实验I:你如何确定控制果蝇翅型的基因位于常染色体上?实验方法:用数量能满足实验要求的纯种残翅果蝇与纯种长翅果蝇做正交和反交实验。对两种不同杂交方式得到的后代性状统计分析。实验结果预测:                                                        。实验结论:控制果蝇翅和身体的基因位于常染色体上。实验II:根据实验I的实验结果和结论,你如何确定长翅为显性性状?实验方法:用数量能满足实验要求的纯种残翅果蝇与纯种长翅果蝇做正交和反交实验。实验结果预测:                                                        。实验结论:果蝇的长翅对残翅为显性。(3)现有两管果蝇,甲管全部为长翅形,乙管既有长翅形,也有残翅形,谁是亲本,可根据试管中果蝇的性别来判断。①若乙管是甲管的亲代,则乙管中                                。②若甲管是乙管的亲代,则乙管中                                。(4)如果已经知道果蝇的刚毛型对截毛型是显性,基因用B和b表示,如何用简单的方法通过一代杂交实验确定基因位于哪种染色体上?(用遗传图解表示并结合文字简单表述)
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