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美国科学60秒 SSS 2013-06-06

时间:2013-07-25 06:20:27

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(单词翻译)

   Most birds don't have penises. Good, I have your attention. Of course, female birds don't have penises. But, neither do most males. Now researchers have unravel1 the genetics behind the dispearance of this anatomical apparatus3. Their penetrating4 insights are in the journal Current Biology. Only 3% of avian species have males with obvious organs of intromission. Ducks and other water fowl5 are fairly well endowed. But most birds have just rudimentary gear, if anything at all. To get rid of this penile puzzle, researchers compared the embryos6 of chickens and ducks. Both types of birds start to develop a member. But in chickens, the so-called 'genital tubercle' shrinks before the little guys hatch. It's because of a gene2 called Bmp4. Bmp4 basically tell cells to comitte suicide. This form of cell death keeps birds from sprouting7 teeth, and in developing male chickens, it causes the phallus to regress. Why this happens is still a mystery. It may allow females birds to be more selective about their mates. Because males with external equipement tend to impose it where they will. Whereas those without have to let the ladies roll the roost.


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1 unravel Ajzwo     
v.弄清楚(秘密);拆开,解开,松开
参考例句:
  • He was good with his hands and could unravel a knot or untangle yarn that others wouldn't even attempt.他的手很灵巧,其他人甚至都不敢尝试的一些难解的绳结或缠在一起的纱线,他都能解开。
  • This is the attitude that led him to unravel a mystery that long puzzled Chinese historians.正是这种态度使他解决了长期以来使中国历史学家们大惑不解的谜。
2 gene WgKxx     
n.遗传因子,基因
参考例句:
  • A single gene may have many effects.单一基因可能具有很多种效应。
  • The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。
3 apparatus ivTzx     
n.装置,器械;器具,设备
参考例句:
  • The school's audio apparatus includes films and records.学校的视听设备包括放映机和录音机。
  • They had a very refined apparatus.他们有一套非常精良的设备。
4 penetrating ImTzZS     
adj.(声音)响亮的,尖锐的adj.(气味)刺激的adj.(思想)敏锐的,有洞察力的
参考例句:
  • He had an extraordinarily penetrating gaze. 他的目光有股异乎寻常的洞察力。
  • He examined the man with a penetrating gaze. 他以锐利的目光仔细观察了那个人。
5 fowl fljy6     
n.家禽,鸡,禽肉
参考例句:
  • Fowl is not part of a traditional brunch.禽肉不是传统的早午餐的一部分。
  • Since my heart attack,I've eaten more fish and fowl and less red meat.自从我患了心脏病后,我就多吃鱼肉和禽肉,少吃红色肉类。
6 embryos 0e62a67414ef42288b74539e591aa30a     
n.晶胚;胚,胚胎( embryo的名词复数 )
参考例句:
  • Somatic cells of angiosperms enter a regenerative phase and behave like embryos. 被子植物体细胞进入一个生殖阶段,而且其行为象胚。 来自辞典例句
  • Evolution can explain why human embryos look like gilled fishes. 进化论能够解释为什么人类的胚胎看起来象除去了内脏的鱼一样。 来自辞典例句
7 sprouting c8222ee91acc6d4059c7ab09c0d8d74e     
v.发芽( sprout的现在分词 );抽芽;出现;(使)涌现出
参考例句:
  • new leaves sprouting from the trees 树上长出的新叶
  • They were putting fresh earth around sprouting potato stalks. 他们在往绽出新芽的土豆秧周围培新土。 来自名作英译部分

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