首页
登录
职称英语
[originaltext]I’ve mentioned how DNA has solved many mysteries in biology. And
[originaltext]I’ve mentioned how DNA has solved many mysteries in biology. And
游客
2023-08-10
62
管理
问题
I’ve mentioned how DNA has solved many mysteries in biology. And today I want to talk about how it might relate to hypothesis about the travels of the green turtle. [23] Every winter some green turtles make a 2,000 km journey from Brazil to Ascension Island in the middle of Atlantic, where they mate and lay eggs. But the question is why do they travel so far to lay their eggs? One researcher hypothesized that there are two parts to the explanation. One is natal homing, [24] the instinct that drives green turtles to always return to the beach where they were hatched. The second part has to do with continental drift, the theory that the positions of earth continents have changed considerably overtime. Brazil and Ascension Island were once much closer together, and continental drift drove them apart. But the turtles kept on going back to the island where they hatched. However another scientist questioned this explanation on the grounds that it would be very unlikely that conditions would allow generations of turtles over hundreds of millions of years to keep going back to the same nesting ground every single year. So, what is the connection to DNA? Well, there are groups of green turtles that nest in locations other than the Ascension Island. If green turtles always return to the place where they were hatched, then the turtles that have been going to the Ascension Island to nest would have been genetically isolated long enough to have DNA that was very different from the green turtles that nest elsewhere. But when scientists examined DNA from these turtles, their DNA wasn’t that different from the DNA of the turtles that go to Ascension Island. Do you have a shock? Well, we still don’t know the answer to the question about why a certain group of turtles go to Ascension Island, but [25] this study was a nice example of the usefulness of DNA analysis to biology.
1.How far do some green turtles travel to lay their eggs?
2.What drives green turtles to return to the beach according to the theory of “natal homing”?
3.What is proved in this study?
选项
A、Climate.
B、Instinct.
C、Temperature.
D、Salinity.
答案
B
解析
转载请注明原文地址:http://tihaiku.com/zcyy/2914806.html
相关试题推荐
[originaltext]Objectsthatarevibratingmakesounds.Rhythmicsoundvibrations
[originaltext]Inorderforachemicaltobeconsideredadrug,itmusthavethe
[originaltext]Inorderforachemicaltobeconsideredadrug,itmusthavethe
[originaltext]Inorderforachemicaltobeconsideredadrug,itmusthavethe
[originaltext]Hi,everybody.AsIsaidinmyStateoftheUnionaddress,weliv
[originaltext]Hi,everybody.AsIsaidinmyStateoftheUnionaddress,weliv
[originaltext]Hi,everybody.AsIsaidinmyStateoftheUnionaddress,weliv
[originaltext]IntheUnitedStates,manypeopleoncelivedinlarge,two-and-th
[originaltext]IntheUnitedStates,manypeopleoncelivedinlarge,two-and-th
[originaltext]W:2millionhighschoolseniorsaregearingupthisfalltoappl
随机试题
Whereistheball?[br][originaltext]M:Whatcanyouseeinthepicture?F:I
红、橙、黄、绿、青、蓝、紫色中,________为暖色.________为冷色。
治疗产褥中暑暑伤津气证,应首选A、白虎汤 B、竹叶石膏汤 C、清暑益气汤
()是指投资者依据公司法,通过出资形成一个独立的公司法人实体,由公司法人实体自
与妊娠高血压综合征发病无关的是A.双胎 B.糖尿病 C.慢性肾炎 D.羊水
具有对自己行为应该负道德责任的自觉认识和自我评价能力的是A.护理伦理良心 B.
饼图、条形图、环形图等仅适用于定性数据。()
干粉灭火系统检查项目中,每年应检查1次的有()。A.防护区及干粉储存装置间
采用()对管理人员进行培训,能够提高其解决问题能力和决策能力。A.事件过程法
根据《放射性污染防治法》,下列矿产资源开发项目中,其环境影响报告书应当报国务院环
最新回复
(
0
)