科學60秒:和藻類共生的蠑螈
來源：滬江聽寫酷
2011-08-03 10:00
A rolling stone gathers no____1____. But a salamander embryo can attract algae. Inside its tissues and cells. This intimate________—the first ever seen between algae and a vertebrate—is revealed in the Proceedings of the National Academy of Sciences.
Spotted salamanders lay their eggs in pools in spring. And the egg ________ actually look green, thanks to the algae that surrounds the resident embryos. That relationship benefits both parties. Algae feed on the nitrogen-rich waste products generated by the embryos. And the embryos bask in the oxygen given off by the algae. Take away their algae, and spotted salamander babies ____4____smaller and less mature.
So that’s the eggs. But this study is the first to show that the algae actually inhabit the embryo itself. Using imaging techniques and DNA testing, scientists found algae inside the cells of young salamander embryos—and even in the reproductive tracts of some adult females. Which suggests that some algae may be handed down directly from parent to child. More evidence that many individuals are really____5____.
【視聽版科學小組榮譽出品】
Spotted salamanders lay their eggs in pools in spring. And the egg ________ actually look green, thanks to the algae that surrounds the resident embryos. That relationship benefits both parties. Algae feed on the nitrogen-rich waste products generated by the embryos. And the embryos bask in the oxygen given off by the algae. Take away their algae, and spotted salamander babies ____4____smaller and less mature.
So that’s the eggs. But this study is the first to show that the algae actually inhabit the embryo itself. Using imaging techniques and DNA testing, scientists found algae inside the cells of young salamander embryos—and even in the reproductive tracts of some adult females. Which suggests that some algae may be handed down directly from parent to child. More evidence that many individuals are really____5____.
【視聽版科學小組榮譽出品】
moss
co-habitation
capsules
hatch
entire little ecosystems
滾石不生苔。但蠑螈胚胎卻會吸引藻類進入組織和細胞。這種親密的共生關系首次見于藻類和脊椎動物之間，文章刊登在《美國科學院院報》上。
斑點蠑螈春天在池塘產(chǎn)卵，卵的表面是綠色的，因為藻類圍繞著在那里安家落戶的胚胎。這種關系對雙方都是有益的。胚胎產(chǎn)生富含氮的廢物是藻類的養(yǎng)料，而藻類產(chǎn)生的氧氣讓胚胎更加舒服。沒有藻類的斑點蠑螈寶寶孵化出來后體型更小，也沒那么成熟。
這就是蠑螈的卵。這項研究首次發(fā)現(xiàn)藻類真正生活在胚胎里面?？茖W家們使用成像技術和DNA檢測發(fā)現(xiàn)，早期蠑螈胚胎細胞和某些成年雌性的生殖道里含有藻類。這表明有些藻類是通過父母傳遞給下一代的。更多證據(jù)顯示，很多個體本身就是一個完整的小型生態(tài)系統(tǒng)。