题干

如图1表示人类镰刀型细胞贫血症的病因,图2是一个家族中该病的遗传系谱图(控制基因为B和b),请据图回答(谷氨酸的密码子是GAA,GAG):

(1)图中①②表示的遗传信息传递过程分别是:①____ ;②____ .①过程发生的时间是____ .

(2)X链碱基组成为____ ,Y链碱基组成为____ .

(3)镰刀型细胞贫血症的致病基因位于____ 染色体上,属于____ 性遗传病.

(4)Ⅱ8基因型是____ ,Ⅱ6和Ⅱ7再生一个正常孩子的概率是____ .

(5)若图中正常基因片段中CTT突变为CTC,由此控制的生物性状是否发生改变____ 原因是____ 

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答案(点此获取答案解析)

\u590d\u5236,\u8f6c\u5f55,\u7ec6\u80de\u5206\u88c2\u95f4\u671f,CAT,GUA,\u5e38,\u9690,BB\u6216Bb,3/4,\u4e0d\u6539\u53d8,\u56e0\u4e3a\u7a81\u53d8\u524d\u540e\u7684\u5bc6\u7801\u5b50\u6240\u51b3\u5b9a\u7684\u6c28\u57fa\u9178\u76f8\u540

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    You might make a disgusted face when you notice that the person waiting in their car at the red light next to you is picking their nose,but admit it,you do it too.And while it might be the natural option when there isn't a box of tissues around,it can be bad for you.The main reasons people feel the need to pick their nose is to clear it of dried liquid,stop an itch(痒),or just because it feels good.Boogers(鼻屎)form when dried liquid and cilia,the tiny hairs that line the nostrils(鼻孔),trap the dust,dirt,and other things.When boogers build up in your nose,it can be uncomfortable,and sometimes just blowing into a tissue doesn't do the trick.

    Otolaryngologist Erich P.Voigt, MD ,told Business Insider that picking your nose can cause injuries and bleeding within your nostrils.That's not terribly damaging,but when the bacteria from your hands get into your body,it can cause a cold and flu.So doctors strongly suggest not picking the nose.

    If dry winter air is causing the dirty liquid to harden in your nostrils,making you want to pick,consider damping the air at home,or taking a steam shower to soften things up in there.

    Children, who are most famous for having a finger up their nose,sometimes don't realize how much injury they're causing,and sometimes it.can lead to nose bleeds.

    So, next time you go to pick your nose,think about how many bacteria are on your hands and in your boogers, and maybe reach for a tissue instead.Even if you 're alone,and not waiting for the light to turn green,please,use a tissue.