北师大版2022到2022高一英语周报26期答案

5.B(根据题意分析可知:果蝇的灰身和黑身由常染色体上的等位基因(B-b)控制,等位基因(R-r)位于X染色体上,说明控制体色的两对等位基因分别位于两对同源染色体上,因此在遗传过程中遵循自由组合定律。纯合的黑身雌果蝇与纯合的灰身雄果蝇杂交,F1全为灰身,子二代中雌、雄果蝇灰身:黑身〓3:1,其中雌果蝇没有深黑身,雄果蝇黑身:深黑身=1:1,说明子一代雄果蝇的基因型是BbXY,雌果蝇的基因型是BbXX,基因R、r中使黑身果蝇的体色加深的是基因r。因此,亲本雄果蝇的基因型是BBⅹY,雌果蝇的基因型是bbXX。现有的雌雄果蝇:亲本BBXY、 bbX R;子一代:BbXY、BbXX";子二代:BBXX、BBXX、BBXY、BBXY、 BbX XBbXX、BbXY、BbXY、bbXX、bbXX、bbXY、bbX"Y。其中能通过一次交配使雌雄子代同时具有三种表现型的杂交组合有以下三种:bbXX与BbXY;bbXY与BbXX;BbXY和BbX“X。故B正确,A、C、D错误。)

第三节One possible wersionParagraph 1Some time later, he woke up under a tree in the samevalley. He was alone, worried about his dog and he knewhe was going to get into more trouble with his wife. Then henoticed a curious thing his hair was over his shouldersand his beard was over a foot long! So strange was he thathe decided immediately to get back to the village. As soonas he got there, he realized that everything was differentand there were lots of new houses. Surprisingly, he didn'trecognize the people in the villageParagraph 2:When he got to his house, he saw that it was old andbandoned. To his sorrow, his wife had died two years before and the two children had left away. Despite the arment with his wife, he was regretful for the past. Facingthis sharp change, Rip was determined to change his way ofliving and never be a lazy man. He became a diligentfarmer and kept pace with the new society. In his sparetime, he would still go to the old inn that had been rebuiltto tell some stories about his adventure in the valley, whichappealedto the children a lo

以上就是北师大版2022到2022高一英语周报26期答案，更多英语周报答案请关注本网站。