两个亲本的基因型分别为AAbb和aaBB,这两对基因按自由组合定律遗传,要培育出基因

题型:单项选择题

问题:

两个亲本的基因型分别为AAbb和aaBB,这两对基因按自由组合定律遗传,要培育出基因型为aabb的新品种,最简捷的方法是()

A.单倍体育种 

B.杂交育种 

C.人工诱变育种 

D.细胞工程育种

考点:自然科学相关工程与技术细胞工程细胞工程题库
题型:单项选择题

单词拼写

小题1:One of the main d_________to their products is that they tend to waste electricity.

小题2:This monument was built in honor of those who s________their lives for the country’s independence.

小题3:Peter stood out among the job hunters because of his c________of English, so the company employed him as a translator.

小题4:I tried to c________in my speech how grateful we all were for his help.

小题5:I believed Mary will turn up at night. I know she is always very ________(准时) for appointments.

小题6:I’m going to show you just a few examples of how common these _________(现象) are.

小题7:I know that if I start watching a soap opera I immediately become hopelessly ________(上瘾)

小题8:There is ___________(大量的) evidence that a person’s character is reflected in their handwriting.

小题9:After her father died, the girl ________(不与人交往) from others and often stayed alone。

小题10:I have been __________(订阅) to this magazine for years.

题型:单项选择题

肾综合征出血热早期出血的原因主要为()

A.尿毒症所致凝血障碍

B.弥散性血管内凝血

C.肝素类物质增加

D.血管脆性增加及血小板减少

E.凝血因子不足

题型:单项选择题

聚合反应体系中热量不能及时移走,而易发生爆聚.

题型:单项选择题

患儿,3岁,以形体消瘦,体重增长缓慢,纳差为主症前来就诊。

患儿若见面色萎黄,毛发枯黄稀疏,精神萎靡,睡卧不宁,五心烦热,盗汗,舌红光剥。应采用哪组处方:()

A.补脾经,推三关,揉外劳,运内八卦,掐揉四横纹,按揉足三里,揉中脘,捏脊

B.补脾经,推三关,揉外劳,运风八卦,掐揉四横纹,按揉足三里,揉中脘,推肺经,推揉膻中,肺俞

C.补脾经,清大肠,按揉百会,掐揉五指节,掐揉小横纹,按揉百会,揉中脘

D.补脾经,运内八卦,掐揉四横纹,按揉足三里,揉中脘,捏脊,清肝经,补肾经,揉上马,运内劳宫

E.补脾经,补肾经,推三关,揉外劳,揉中脘,揉脐,按揉足三里

题型:单项选择题

净空道的起点应位于()的末端。宽度应自跑道中线延长线向两侧延伸不少于()米。

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