SSS 2011-04-15_在线英语听力室_免费在线英语听力学习网站

(单词翻译:双击或拖选)

This is Scientific American's 60-Second Science. I'm Christopher Intagliata. Got a minute?

When your stomach's empty, it pumps out the hormone¹ ghrelin, to whet² your appetite and get your juices flowing. But ghrelin doesn't just make you crave³ a bite. It helps you track it down too—by sharpening your sense of smell. That's according to a study out this week in the Journal of Neuroscience.

First, scientists injected rats with ghrelin, and videotaped their noses. Their sniffers ran on overdrive for several hours following the injection. And the rats could detect fainter scents⁴, too.

So then the researchers called in nine fasting humans, to see if our sniffing⁵ powers get a boost from ghrelin. The volunteers took whiffs of various substances—like baby powder, tomatoes and rosemary chicken. And regardless of how appetizing each aroma⁶ was, the volunteers took deeper whiffs—even of plain air—after getting a shot of ghrelin.

All of which suggests we've evolved a number of tricks to avoid the ultimate game-over: starvation. Because knowing you're famished⁷ is only half the battle. Actually tracking down that wooly⁸ mammoth⁹? That’s what really counts.

Thanks for the minute. For Scientific American's 60-Second Science, I'm Christopher Intagliata.

点击

收听单词发音

1 hormone
n.荷尔蒙，激素，内分泌
参考例句：
Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。 This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。

2 whet
v.磨快，刺激
参考例句：
I've read only the fIrst few pages of her book,but It was enough to whet my appetIte.她的书我只看了开头几页，但已经引起我极大的兴趣。 A really good catalogue can also whet customers' appetites for merchandise.一份真正好的商品目录也可以激起顾客购买的欲望。

3 crave
vt.渴望得到，迫切需要，恳求，请求
参考例句：
Many young children crave attention.许多小孩子渴望得到关心。 You may be craving for some fresh air.你可能很想呼吸呼吸新鲜空气。

4 scents
n.香水( scent的名词复数 )；气味；（动物的）臭迹；（尤指狗的）嗅觉
参考例句：
The air was fragrant with scents from the sea and the hills. 空气中荡漾着山和海的芬芳气息。 The winds came down with scents of the grass and wild flowers. 微风送来阵阵青草和野花的香气。来自《简明英汉词典》

5 sniffing
n.探查法v.以鼻吸气，嗅，闻( sniff的现在分词 )；抽鼻子（尤指哭泣、患感冒等时出声地用鼻子吸气）；抱怨，不以为然地说
参考例句：
We all had colds and couldn't stop sniffing and sneezing. 我们都感冒了，一个劲地抽鼻子，打喷嚏。 They all had colds and were sniffing and sneezing. 他们都伤风了，呼呼喘气而且打喷嚏。来自《现代英汉综合大词典》

6 aroma
n.香气，芬芳，芳香
参考例句：
The whole house was filled with the aroma of coffee.满屋子都是咖啡的香味。 The air was heavy with the aroma of the paddy fields.稻花飘香。

7 famished
adj.饥饿的
参考例句：
When's lunch?I'm famished!什么时候吃午饭？我饿得要死了！ My feet are now killing me and I'm absolutely famished.我的脚现在筋疲力尽，我绝对是极饿了。

8 wooly
adj.毛茸茸的；糊涂的
参考例句：
I like the feel of this cloth and it has a warm wooly feel.我喜欢这块布的手感,它摸上去毛茸茸的很暖和。 He wore a brown t-shirt with jeans and a pair of shoes,with a wooly hat covering his hair.小贝身穿一件棕色t恤，搭配牛仔裤和皮鞋，头戴一顶盖住头发的羊毛帽子。

9 mammoth
n.长毛象；adj.长毛象似的，巨大的
参考例句：
You can only undertake mammoth changes if the finances are there.资金到位的情况下方可进行重大变革。 Building the new railroad will be a mammoth job.修建那条新铁路将是一项巨大工程。