英语听力文摘 English Digest 653 冰河时代的植物存活到现在
时间:2018-12-31 作者:英语课 分类:英语听力文摘 English Digest
英语课
Ice Age Plant Survives To Modern Day
Like a science fiction time traveler, an arctic plant of the late Pleistocene age, over thirty one thousand years old, is growing again after a long frozen sleep.
History
Narrow leafed campion (Silene stenophylla) is a small plant whose modern relatives are found in eastern Russia and northern Japan. It’s a perennial 1 species that grows on stony 2 cliffs or sandy shores. Once a year, it produces five-petalled flowers that range in color from white to pink to lilac.
Russian scientists examining an ancient arctic squirrel burrow 3 recovered ancient campion fruits from the sediments 4. Curious to see if the fruits’ seeds might germinate 5, they planted them. The seeds didn’t grow, but the scientists weren’t discouraged.
Frozen Experiment
They knew an ancient sacred lotus dating back twelve hundred years had been restored. Why not the campion? They decided 6 to try growing a new plant from fruit tissue. It had been frozen all those years, so some cells might be viable 7.
By bathing the fruit tissue in a culture solution with growth hormones 8, similar to a technique commonly used to start plants from cuttings, the scientists were able to restart cell division and get several plants to grow.
Success
The plants not only flourished, they produced flowers. The flowers went on to produce fruit and seeds that were viable and germinated 9 into a second generation of plants. The ancient campion was given a second chance at life.
As the earth warms and more and more arctic permafrost melts, larger numbers of ancient plants will be exposed, giving us a chance to bring plants of the ancient past back to life. And who knows, one day we might resurrect a mammoth 10 to eat them.
冰河时代的植物存活到现在
犹如科幻小说里的时间旅行者,一种曾存活在更新世晚期的极地植物经过31000多年的冰封沉睡之后,再次得以生长。
历史
窄叶剪秋萝(柳叶蝇子草)是一种小型植物,它们的现代近亲生活在俄罗斯东部与日本北部。它是一种多年生植被,生长在石崖或砂质海滨。它每年开花一次,花朵有五片花瓣,花色有白色,粉色,还有丁香紫色。
俄罗斯科学家在北极科考一处古代松鼠的洞穴时,在其沉淀物中获得了剪秋萝的果实。出于好奇,科学家们想知道果实中的种子是否可以发芽,因此他们种下了种子。
冰冻实验
科学家们获悉有一株1200年前的古代圣莲获得新生,那剪秋萝为什么不可以呢?他们决定通过果实组织成分培育一株新植物。果实已被冷冻多年,因此有部分细胞应该得以存活。
将果实组织浸泡在含生长激素的营养液中(这种培育方式类似于植物的扦插),科学家们能够重建细胞分裂,从而让许多植物得以生长。
成功
这些剪秋萝不仅枝叶茂盛,而且开花结果,种籽继续发芽繁殖出下一代。古老的剪秋萝重获生命。
随着全球变暖,更多的极地冰川融化,会有更多的古代植物重见天日,这也给予了我们重新培植这些植物的机会。也许有一天,我们能够让猛犸象复生,让这些植物成为猛犸象的美餐,谁知道呢?
adj.终年的;长久的
- I wonder at her perennial youthfulness.我对她青春常驻感到惊讶。
- There's a perennial shortage of teachers with science qualifications.有理科教学资格的老师一直都很短缺。
adj.石头的,多石头的,冷酷的,无情的
- The ground is too dry and stony.这块地太干,而且布满了石头。
- He listened to her story with a stony expression.他带着冷漠的表情听她讲经历。
vt.挖掘(洞穴);钻进;vi.挖洞;翻寻;n.地洞
- Earthworms burrow deep into the subsoil.蚯蚓深深地钻进底土。
- The dog had chased a rabbit into its burrow.狗把兔子追进了洞穴。
沉淀物( sediment的名词复数 ); 沉积物
- When deposited, 70-80% of the volume of muddy sediments may be water. 泥质沉积物沉积后,体积的70-80%是水。
- Oligocene erosion had truncated the sediments draped over the dome. 覆盖于穹丘上的沉积岩为渐新世侵蚀所截削。
v.发芽;发生;发展
- Seeds will not germinate without water.没有水,种子是不会发芽的。
- Can thin and hollow seeds germinate?瘦瘪的种子能够发芽吗?
adj.决定了的,坚决的;明显的,明确的
- This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
- There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。
adj.可行的,切实可行的,能活下去的
- The scheme is economically viable.这个计划从经济效益来看是可行的。
- The economy of the country is not viable.这个国家经济是难以维持的。
v.(使)发芽( germinate的过去式和过去分词 )
- First, the researchers germinated the seeds. 研究人员首先让种子发芽。 来自辞典例句
- In spring they are germinated and grown for a year in beds. 春季里,他们在苗床发芽并生长一年。 来自辞典例句