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【单选题】

C With only about 1,000 pandas left in the world, China is desperately trying to clone the animal and save the enered species. That’s a move similar to what a Texas A&M University researcher has been undertaking for the past five years in a project called "Noah’s Ark". Dr. Duane Kraemer, a professor in Texas A & M’s College of Veterinary Medicine and a pioneer in embryo(胚胎) transfer work and related procedures, says he salutes the Chinese effort and" I wish them all the best success possible. It’s a worthwhile project, certainly not an easy one, and it’s very much like what we’re attempting here at Texas A&M--to save animals from extinction. " Noah’s Ark is aimed at collecting eggs, embryos, semen(精子) and DNA of enered animals and storing them in liquid nitrogen. If certain species should become extinct, Kraemer says there would be enough of the basic building blocks to reintroduce the species in the future. It is estimated that as many as 2,000 species of mammals, birds and reptiles will become extinct over the next 100 years. The panda, native only to China, is in er of becoming extinct in the next 25 years. This week, Chinese scientists said they grew an embryo by introducing cells from a dead female panda into the egg cells of a Japanese white rabbit. They are now trying to implant the embryo into a host animal. The entire procedure could take from three to five years to complete. "The nuclear transfer of one species to another is not easy, and the lack of available panda eggs could be a major problem," Kraemer believes. "They will probably have to do several hundred transfers to result in one pregnancy. It take s a long time and it’s difficult, but this could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it is worth the effort , "adds Kraemer, who is one of the leaders of the Missyplicity Project at Texas A&M, the first ever attempt at cloning a dog. "They are trying to do something that’s never been done, and this is very similar to our work in Noah’s Ark. We’re both trying to save animals that face extinction. I certainly applaud their effort and there’s a lot we can learn from what they are attempting to do. It’s a research that is very much needed. " The word "groundbreaking" (Paragraph 7) can be interpreted as ______.

A.
essentially new
B.
pioneering
C.
evolutionary
D.
epoch--
题目标签:胚胎
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【单选题】胚胎工程技术在生产中的应用不包括[ ]

A.
移植胚胎干细胞使退化的组织修复并恢复正常功能
B.
进行胚胎移植充分发挥雌性优良个体的繁殖潜能
C.
采用机械方法将早期胚胎分割产生同卵双胎
D.
在小鼠腹腔中培育杂交瘤细胞生产单克隆抗体

【单选题】睾丸下降开始于胚胎第( )

A.
5个月
B.
6个月
C.
7个月
D.
8个月
E.
9个月

【单选题】甲状腺形成的时间是胚胎

A.
第四周
B.
第五周
C.
第六周
D.
第七周
E.
第八周

【单选题】有胚胎毒性的中药是

A.
白术
B.
葛根
C.
当归
D.
泽泻
E.
半夏

【单选题】胚胎早期的神经管由内向外依次为

A.
室管膜层、套层和边缘层
B.
套层、边缘层和室管膜层
C.
边缘层、套层和室管膜层
D.
室管膜层、边缘层和套层
E.
套层、室管膜层和边缘层