首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
A、Teach their young how to swim. B、Mate and lay eggs. C、Hide from predators. D、Eat different kinds of fish. BWhat?do?green?turtl
A、Teach their young how to swim. B、Mate and lay eggs. C、Hide from predators. D、Eat different kinds of fish. BWhat?do?green?turtl
admin
2013-04-25
41
问题
I’ve mentioned how DNA have 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. Every winter some green turtles make a 2000 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, 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 question this explanation on the ground that it would be very unlikely that conditions would allowe 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’ve been genetically isolated long enough to have DNA that was very different from the green turtles that nest else where. But when scientists examine 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 this study was a nice example of the usefulness of DNA analysis to biology.
选项
A、Teach their young how to swim.
B、Mate and lay eggs.
C、Hide from predators.
D、Eat different kinds of fish.
答案
B
解析
What?do?green?turtles?do?when?they?get?to?Ascension?Island?
转载请注明原文地址:https://kaotiyun.com/show/tSyO777K
0
托福(TOEFL)
相关试题推荐
SECTION3Questions21-30Questions21-23CompletethenotesonwhatMikasaysatthebeginningofthediscussion.Mikasays
Theuniversityhasproduceda______toinformstudentsaboutthedifferentaccommodationoptionsavailable.GrampianHalls
Questions11-14CompletethefollowingsentencesusingNOMORETHANTHREEWORDSforeachgap.
YoucanbuyPhonecardsofdifferent______fromvariousshops.
SECTION4Questions31-40Questions31-33CompletethefollowingnotesondifferencesyoumightnoticewhenyougohomeusingNO
WhatisthepurposeofJaneandRick’smeetingwiththetutor?
WhatisthepurposeofJaneandRick’smeetingwiththetutor?
Thefollowingareessentialrequirementsforwhichjobs?Writethecorrectletter,A,BorC,nexttoquestions11-15.
Whichattitudeisassociatedwiththefollowingpeopleduringtheconversation?ChooseSIXanswersfromtheboxandwritetheco
Asyourinstructoradvised,yououghttospendyourtimeonsomething______researchinginto.
随机试题
依据JJF1059.1-2012,当对输入量的分布缺乏任何信息的情况下,一般假设该量服从________。
男性患儿,8岁。因发热、头痛、皮疹3天入院。查体:急性病容,皮疹出现于躯干、头面部、四肢近端。可见红斑疹、丘疹、疱疹、脓疱疹不同形态的皮疹,个别皮疹已结痂。血象:白细胞总数为4.2×109/L。患儿同学中有类似的病人。相关疾病的防治措施正确的是
开户单位现金收入应于当日送存银行,当日送存确有困难的,由()确定送存时间。
构建社会主义和谐社会的主要动力是
(91年)求微分方程xy’+y=xex满足y(1)=1的特解.
以下不属于Python机器学习领域的第三方库的是()。
函数fun的功能是:把形参a所指数组中的最大值放在a[0]中,接着求出a所指数组中的最小值放在a[1]中:再把a所指数组元素中的次大值放在a[2]中,把a数组元素中的次小值放在a[3]中;其余以此类推。例如:若a所指数组中的数据最初排列为:1、4、2、3、
下列属性中,属于窗体的“数据”类属性的是()。
Whatdidthewomanfind?
Therearetwobasicwaystoseegrowth:oneasaproduct,theotherasaprocess.Peoplehavegenerallyviewedpersonalgrowtha
最新回复
(
0
)