美国科学60秒 SSS 2015-04-09
时间：2019-01-20 作者：英语课 分类：2015年Scientific American(四)月
英语课
Telomeres are parts of chromosomes 1 that protect the ends of the chromosomes. They’re often likened to the aglets(绳两端的金属箍) at the end of shoelaces(鞋带). And like aglets eventually crack, telomeres tended to get shorter over time, with each division of the cell. But they can be topped off again by an enzyme 2 called telomerase reverse transcriptase. Various age-related diseases are associated with shortened telomeres.
Elizabeth Blackburn won a Nobel Prize for her discoveries about telomeres and the telomerase enzyme. She recently did a Google Hangout(视频群聊) with Scientific American editor-in-chief Mariette DiChristina which included taking questions from attendees(参加者) via social media.
“Can telomeres actually grow longer and response to exercise?”
“Well, we don’t know if telomeres actually grow with exercise, but what is known is, I’ll give you a great example of a study. We didn’t do it. Twins. So they looked at twins. This is a big study. And they said, of the twin who’ve actually done exercise, the one who did exercise and the one who didn’t, so you’d be able to find a lot of twins it turns out, in that situation. And they said, who’s got the longer telomeres. And it was twin who did some exercise. The one who didn’t had shorter telomeres. And yet their genes 3 are the same. So you see that tells you something quite nice.
And of course, well, you say, was it really the exercise, or was it something else that was different between the twins. And that’s where epidemiology studies have to be done so carefully. But over and over again, we keep finding that same result. That the exercise, is associated with a personal who will have less telomere shortening. And so it looks like now, it really is the exercise that’s somehow keeping the shortening process from being too fast.”
The entire 27-minute Google Hangout with Mariette DiChristina and Nobel Laurent Elizabeth Blackburn is on our website. Just google “Hangout” and “Elizabeth Blackburn”.
n.染色体( chromosome的名词复数 )
- Chromosomes also determine the sex of animals. 染色体也决定动物的性别。 来自《简明英汉词典》
- Each of four chromosomes divide longitudinally. 四种染色体的每一种都沿着纵向分裂。 来自《现代汉英综合大词典》
n.酵素，酶
- Above a certain temperature,the enzyme molecule will become unfolded.超过一定温度，酶分子将会展开。
- An enzyme that dissolves the fibrin of blood clots.能溶解血凝块中的纤维的酶。