在托福听力考试的备考过程中，科学美国人60秒相信大家一定用得比较多，那么大家平时是如何利用这个课外资料的呢?这里小编整理了科学美国人60秒无核水果科学研究的内容分享，大家一起来学习一下吧。

科学美国人60秒听力练习：无核水果科学研究

科学美国人60秒英文文本

Mark Twain called it “the most delicious fruit known to men.” He was talking about the cherimoya. If you never heard of it, there’s good reason. It has a feature that has prevented it from becoming widely popular—numerous big seeds fill its sweet white flesh.

But now scientists in Spain and at the University of California, Davis, have found the key to making the cherimoya and related fruits seedless. They published their research in the Proceedings of the National Academy of Sciences. [Jorge Lora et al., "Seedless fruits and the disruption of a conserved genetic pathway in angiosperm ovule development"]

It’s generally tough to develop a seedless fruit—bananas and oranges are rare successes. Breeding for seedlessness usually fails to produce the fully developed fruit consumers demand. But the scientists found a spontaneous mutation that causes seedlessness in a cherimoya relative, the sugar apple. They compared its genome to that of a seedless mutant of a plant called Arabidopsis that’s used in a lot of research.

In both cases, they found a deletion of one particular gene. The researchers say this is the first time a gene for seedlessness has been determined. If they can find a way to knock out that gene in the cherimoya, it could bring Mark Twain’s favorite fruit, and many others, to a grocery store near you.

—Cynthia Graber

科学美国人60秒中文翻译：

马克吐温所说的“人类所知的最鲜美的水果”，指的是番荔枝。如果你从没听说过它，也不必觉得自己孤陋寡闻。这种水果本身的一种特性使它无法被广泛种植——它甜美的白色果肉里塞满了大大的果核。

但如今西班牙与加利福尼亚大学的科学家们，戴维斯发现了使番荔枝及相关水果成为无核水果的关键。他们的研究成果将刊登在《全国科学院学报》上。(乔治 洛拉等，无核水果与被子植物胚珠发育过程中遗传途径的破坏

开发一种无核水果是十分困难的——香蕉和橘子是鲜有的成功先例。培育无核水果的结果通常是无法生产消费者需要的发育完全的水果。但科学家们发现了一种自发突变，可使番荔枝的近亲，一种叫释迦的水果，变成无核水果。他们将释迦的染色体组跟拟南芥的无核突变体进行比较，后者常用于各种实验中。

在比较中，科学家们发现这两种突变体都舍弃了一个同样的基因。研究人员们说这还是首次确认无核水果的一种基因。如果他们能找到一个方法去掉番荔枝中的这种基因，那这个马克吐温最爱的水果，及其他各种水果，都能来到你的身旁。

——辛西娅 格蕾伯

1. cherimoya n. [植]番荔枝(产于南美), 番荔枝之果

2. seedless adj. 无核的, 无籽的

3. mutation n.突变，变异

4. genome n. 基因组, 染色体组

5. deletion n. 缺失

以上就是小编为大家整理的科学美国人60秒：无核水果科学研究的文本以及翻译，大家练习的时候还可以找来音频资料一起练习，效果定会更好。最后，小编预祝大家托福考试能取得理想的成绩。