An appropriate title for the text is most likely to be__________.[A]Fors and Againsts of DNA testing[B] DNA testing and It’s problems[C]DNA testing outside the lab[D] lies behind DNA testing

It is a wise father that knows his own child,but today a man can boost his paternal（fatherly）wisdom–or at least confirm that he's the kid's dad.All he needs to do is shell our$30 for paternity testing kit（PTK）at his local drugstore–and another$120 to get the results.More than 60,000 people have purchased the PTKs since they first become available without prescriptions last years,according to Doug Fog,chief operating officer of Identigene,which makes the over-the-counter kits.More than two dozen companies sell DNA tests Directly to the public,ranging in price from a few hundred dollars to more than$2,500.Among the most popular:paternity and kinship testing,which adopted children can use to find their biological relatives and families can use to track down kids put up for adoption.DNA testing is also the latest rage among passionate genealogists—and supports businesses that offer to search for a family's geographic roots.Most tests require collecting cells by swabbing saliva in the mouth and sending it to the company for testing.All tests require a potential candidate with whom to compare DNA.But some observers are skeptical,"There is a kind of false precision being hawked by people claiming they are doing ancestry testing,"says Trey Duster,a New York University sociologist.He notes that each individual has many ancestors-numbering in the hundreds just a few centuries back.Yet most ancestry testing only considers a single lineage,either the Y chromosome inherited through men in a father's line or mitochondrial DNA,which is passed down only from mothers.This DNA can reveal genetic information about only one or two ancestors,even though,for example,just three generations back people also have six other great-grandparents or,four generations back,14 other great-great-grandparents.Critics also argue that commercial genetic testing is only as good as the reference collections to which a sample is compared.Databases used by some companies don't rely on data collected systematically but rather lump together information from different research projects.This means that a DNA database may have a lot of data from some regions and not others,so a person’s test results may differ depending on the company that processes the results.In addition,the computer programs a company uses to estimate relationships may be patented and not subject to peer review or outside evaluation.27.PTK is used to__________.

A.locate one's birth place
B.promote genetic research
C.identify parent-child kinship
D.choose children for adoption

It is a wise father that knows his own child,but today a man can boost his paternal（fatherly）wisdom–or at least confirm that he's the kid's dad.All he needs to do is shell our$30 for paternity testing kit（PTK）at his local drugstore–and another$120 to get the results.More than 60,000 people have purchased the PTKs since they first become available without prescriptions last years,according to Doug Fog,chief operating officer of Identigene,which makes the over-the-counter kits.More than two dozen companies sell DNA tests Directly to the public,ranging in price from a few hundred dollars to more than$2,500.Among the most popular:paternity and kinship testing,which adopted children can use to find their biological relatives and families can use to track down kids put up for adoption.DNA testing is also the latest rage among passionate genealogists—and supports businesses that offer to search for a family's geographic roots.Most tests require collecting cells by swabbing saliva in the mouth and sending it to the company for testing.All tests require a potential candidate with whom to compare DNA.But some observers are skeptical,"There is a kind of false precision being hawked by people claiming they are doing ancestry testing,"says Trey Duster,a New York University sociologist.He notes that each individual has many ancestors-numbering in the hundreds just a few centuries back.Yet most ancestry testing only considers a single lineage,either the Y chromosome inherited through men in a father's line or mitochondrial DNA,which is passed down only from mothers.This DNA can reveal genetic information about only one or two ancestors,even though,for example,just three generations back people also have six other great-grandparents or,four generations back,14 other great-great-grandparents.Critics also argue that commercial genetic testing is only as good as the reference collections to which a sample is compared.Databases used by some companies don't rely on data collected systematically but rather lump together information from different research projects.This means that a DNA database may have a lot of data from some regions and not others,so a person’s test results may differ depending on the company that processes the results.In addition,the computer programs a company uses to estimate relationships may be patented and not subject to peer review or outside evaluation.29.In the last paragraph,a problem commercial genetic testing faces is__________

A.disorganized data collection
B.overlapping database building
C.excessive sample comparison
D.lack of patent evaluation

共用题干
第二篇

DNA Fingerprinting

DNA is the genetic material found within the cell nuclei of all living things. In mammals（哺乳动物）
the strands of DNA are grouped into structures called chromosomes（染色体）.With the exception of identical
twins,the complete DNA of each individual is unique.
DNA fingerprinting is sometimes called DNA typing. It is a method of identification that compares bits
of DNA.A DAN fingerprint is constructed by first drawing out a DNA sample from body tissue or fluid such
as hair , blood，or saliva（唾液）.The sample is then segmented using enzymes（酶）,and the segments are
arranged by size.The segments are marked with probes and exposed on X-ray film,where they form a pat-
tern of black bars一the DNA fingerprint.If the DNA fingerprints produced from two different samples match,
the two samples probably came from the same person.
DNA fingerprinting was first developed as an identification technique in 1985.Originally used to detect
the presence of genetic diseases,it soon came to be used in criminal investigations and legal affairs.The first
criminal conviction based on DNA evidence in the United States occurred in 1988.In criminal investiga-
tions,DNA fingerprints derived from evidence collected at the crime scene are compared to the DNA finger-
prints of suspects.Generally,courts have accepted the reliability of DNA testing and admitted DNA test re-
sults into evidence.However,DNA fingerprinting is controversial in a number of areas:the accuracy of the
results,the cost of testing,and the possible misuse of the technique.
The accuracy of DNA fingerprinting has been challenged for several reasons. First,because DNA segments
rather than complete DNA strands are"fingerprinted";a DNA fingerprint may not be unique;large-scale
research to confirm the uniqueness of DNA fingerprinting.test results has not been conducted.In addition,
DNA fingerprinting is often done in private laboratories that may not follow uniform testing standards and
quality controls.Also,since human beings must interpret the test,human error could lead to false results.
DNA fingerprinting is expensive.Suspects who are unable to provide their own DNA to experts may not
be able to successfully defend themselves against charges based on DNA evidence.
Widespread use of DNA testing for identification purposes may lead to the establishment of a DNA
fingerprint database.

If two sisters are identical twins,their complete DNAs arev________.
A:the same
B:unique
C:different
D:similar

共用题干
第二篇

DNA Fingerprinting

DNA is the genetic material found within the cell nuclei of all living things. In mammals（哺乳动物）
the strands of DNA are grouped into structures called chromosomes（染色体）.With the exception of identical
twins,the complete DNA of each individual is unique.
DNA fingerprinting is sometimes called DNA typing. It is a method of identification that compares bits
of DNA.A DAN fingerprint is constructed by first drawing out a DNA sample from body tissue or fluid such
as hair , blood，or saliva（唾液）.The sample is then segmented using enzymes（酶）,and the segments are
arranged by size.The segments are marked with probes and exposed on X-ray film,where they form a pat-
tern of black bars一the DNA fingerprint.If the DNA fingerprints produced from two different samples match,
the two samples probably came from the same person.
DNA fingerprinting was first developed as an identification technique in 1985.Originally used to detect
the presence of genetic diseases,it soon came to be used in criminal investigations and legal affairs.The first
criminal conviction based on DNA evidence in the United States occurred in 1988.In criminal investiga-
tions,DNA fingerprints derived from evidence collected at the crime scene are compared to the DNA finger-
prints of suspects.Generally,courts have accepted the reliability of DNA testing and admitted DNA test re-
sults into evidence.However,DNA fingerprinting is controversial in a number of areas:the accuracy of the
results,the cost of testing,and the possible misuse of the technique.
The accuracy of DNA fingerprinting has been challenged for several reasons. First,because DNA segments
rather than complete DNA strands are"fingerprinted";a DNA fingerprint may not be unique;large-scale
research to confirm the uniqueness of DNA fingerprinting.test results has not been conducted.In addition,
DNA fingerprinting is often done in private laboratories that may not follow uniform testing standards and
quality controls.Also,since human beings must interpret the test,human error could lead to false results.
DNA fingerprinting is expensive.Suspects who are unable to provide their own DNA to experts may not
be able to successfully defend themselves against charges based on DNA evidence.
Widespread use of DNA testing for identification purposes may lead to the establishment of a DNA
fingerprint database.

DNA fingerprinting is a technique of________.
A:grouping DNA strands into structures
B:segmenting DNA with probes
C:constructing body tissues by enzymes
D:identifying a person by comparing DNAs

The stages within the development phase of the software life cycle are（ ）．
软件生命周期开发阶段的阶段是

A.design,analysis,implementation,and testing
设计、分析、实现和测试
B.analysis,design,implementation,and testing
分析、设计、实现和测试
C.analysis,design,testing,and implementation
分析、设计、测试和实现
D.design,analysis,testing,and implementation
设计、分析、测试和实现

共用题干
第一篇

DNA Testing

DNA testing reveals the genes of each individual person.Since the early twentieth century scientists
have known that all human characteristics are contained in a person's genes and are passed from parents to
children.Genes work as a chemical instruction manual for each part and each function of the body.Their
basic chemical element is called DNA,a copy of which can be found in every cell. The existence of genes
and the chemical structure of DNA were understood by the mid-1900s,but scientists have only recently been
able to identify a person from just a drop of blood or a single hair.
One of the most important uses of DNA testing is in criminal investigation.The very first use of DNA
testing in a criminal case was in 1985 in Great Britain,when a man confessed to killing a young woman in
the English countryside.Because police had found samples of the killer's DNA at the scene of the crime,a
biologist suggested that it might be possible to compare that DNA to some from the confessor's blood.To
everyone's surprise,the tests showed that he was not the killer. Nor was he guilty of a similar murder that
had happened some time earlier. At that point he admitted that he had confessed to the crimes out of fear
and police pressure.The police then asked 5,000 local men for samples of their blood,and DNA testing
revealed that one of them was the real murderer,so the first man was set free.
In 1992,two law professors,Peter Neufeld and Bany Scheck,decided to use DNA evidence to help set free
such mistakenly convicted prisoners.With the help of their students.they created a not-for-profit organization
called the Innocence Project. Most of their clients are poor men,many from racial and ethnic minorities.In
fact,studies have shown that U. S. judges and juries are often influenced by racial and ethnic background,and
that people from minority groups are more likely to be convicted. Some of these men had been sentenced to
death,a form of punishment used in thirty eight states out of fifty(as of 2006).For most of these prisoners,their
only hope was another trial in which DNA testing could be used to prove their innocence.
Between 1992 and 2006,the Innocence Project helped free 100 men.Some of these prisoners had been
in jail for ten,twenty years or more for crimes they did not commit.However,the goal of the Innocence
Project is not simply to set free those who are wrongfully in jail.They also hope to bring about real changes
in the criminal justice system.
Illinois in the late 1990s,a group of journalism students at Northwestern University were able to bring
about such a change in that state.They began investigating some Illinois prisoners who claimed to be inno-
cent. Through DNA testing,the students were able to prove that in fact the prisoners were not guilty of the
crimes they had been accused of. Thirteen of these men were set free,and in 2000,Governor Ryan of
Illinois decided to stop carrying out death sentences until further study could be made of the prisoners'
cases。
The use of DNA in criminal cases is still being debated around the world.Some fear that governments
will one day keep records of everyone'sDNA,which could put limits on the privacy and freedom of citizens.
Other people mistrust the science of DNA testing and think that lawyers use it to get their clients free whether
or not they are guilty.But for those whose innocence has been proven and who are now free men,DNA
testing has meant nothing less than a return to life.And with the careful use of DNA testing,no innocent
person should ever be convicted again.

What is the main idea of this passage?
A:DNA testing has changed the American legal system.
B:DNA testing has helped innocent men go free in Illinois.
C:DNA testing uses genetics to identify a person.
D:DNA testing has played a key role in criminal investigation.

共用题干
第一篇

DNA Testing

DNA testing reveals the genes of each individual person.Since the early twentieth century scientists
have known that all human characteristics are contained in a person's genes and are passed from parents to
children.Genes work as a chemical instruction manual for each part and each function of the body.Their
basic chemical element is called DNA,a copy of which can be found in every cell. The existence of genes
and the chemical structure of DNA were understood by the mid-1900s,but scientists have only recently been
able to identify a person from just a drop of blood or a single hair.
One of the most important uses of DNA testing is in criminal investigation.The very first use of DNA
testing in a criminal case was in 1985 in Great Britain,when a man confessed to killing a young woman in
the English countryside.Because police had found samples of the killer's DNA at the scene of the crime,a
biologist suggested that it might be possible to compare that DNA to some from the confessor's blood.To
everyone's surprise,the tests showed that he was not the killer. Nor was he guilty of a similar murder that
had happened some time earlier. At that point he admitted that he had confessed to the crimes out of fear
and police pressure.The police then asked 5,000 local men for samples of their blood,and DNA testing
revealed that one of them was the real murderer,so the first man was set free.
In 1992,two law professors,Peter Neufeld and Bany Scheck,decided to use DNA evidence to help set free
such mistakenly convicted prisoners.With the help of their students.they created a not-for-profit organization
called the Innocence Project. Most of their clients are poor men,many from racial and ethnic minorities.In
fact,studies have shown that U. S. judges and juries are often influenced by racial and ethnic background,and
that people from minority groups are more likely to be convicted. Some of these men had been sentenced to
death,a form of punishment used in thirty eight states out of fifty(as of 2006).For most of these prisoners,their
only hope was another trial in which DNA testing could be used to prove their innocence.
Between 1992 and 2006,the Innocence Project helped free 100 men.Some of these prisoners had been
in jail for ten,twenty years or more for crimes they did not commit.However,the goal of the Innocence
Project is not simply to set free those who are wrongfully in jail.They also hope to bring about real changes
in the criminal justice system.
Illinois in the late 1990s,a group of journalism students at Northwestern University were able to bring
about such a change in that state.They began investigating some Illinois prisoners who claimed to be inno-
cent. Through DNA testing,the students were able to prove that in fact the prisoners were not guilty of the
crimes they had been accused of. Thirteen of these men were set free,and in 2000,Governor Ryan of
Illinois decided to stop carrying out death sentences until further study could be made of the prisoners'
cases。
The use of DNA in criminal cases is still being debated around the world.Some fear that governments
will one day keep records of everyone'sDNA,which could put limits on the privacy and freedom of citizens.
Other people mistrust the science of DNA testing and think that lawyers use it to get their clients free whether
or not they are guilty.But for those whose innocence has been proven and who are now free men,DNA
testing has meant nothing less than a return to life.And with the careful use of DNA testing,no innocent
person should ever be convicted again.

What is the author's attitude toward DNA testing?
A:Negative.
B:Positive.
C:Suspicious.
D:Indifferent.

It is a wise father that knows his own child,but today a man can boost his paternal（fatherly）wisdom–or at least confirm that he's the kid's dad.All he needs to do is shell our$30 for paternity testing kit（PTK）at his local drugstore–and another$120 to get the results.More than 60,000 people have purchased the PTKs since they first become available without prescriptions last years,according to Doug Fog,chief operating officer of Identigene,which makes the over-the-counter kits.More than two dozen companies sell DNA tests Directly to the public,ranging in price from a few hundred dollars to more than$2,500.Among the most popular:paternity and kinship testing,which adopted children can use to find their biological relatives and families can use to track down kids put up for adoption.DNA testing is also the latest rage among passionate genealogists—and supports businesses that offer to search for a family's geographic roots.Most tests require collecting cells by swabbing saliva in the mouth and sending it to the company for testing.All tests require a potential candidate with whom to compare DNA.But some observers are skeptical,"There is a kind of false precision being hawked by people claiming they are doing ancestry testing,"says Trey Duster,a New York University sociologist.He notes that each individual has many ancestors-numbering in the hundreds just a few centuries back.Yet most ancestry testing only considers a single lineage,either the Y chromosome inherited through men in a father's line or mitochondrial DNA,which is passed down only from mothers.This DNA can reveal genetic information about only one or two ancestors,even though,for example,just three generations back people also have six other great-grandparents or,four generations back,14 other great-great-grandparents.Critics also argue that commercial genetic testing is only as good as the reference collections to which a sample is compared.Databases used by some companies don't rely on data collected systematically but rather lump together information from different research projects.This means that a DNA database may have a lot of data from some regions and not others,so a person’s test results may differ depending on the company that processes the results.In addition,the computer programs a company uses to estimate relationships may be patented and not subject to peer review or outside evaluation.An appropriate title for the text is most likely to be__________.

A.Fors and Againsts of DNA testing
B.DNA Testing and It's Problems
C.DNA Testing Outside the Lab
D.Lies Behind DNA Testing

It is a wise father that knows his own child,but today a man can boost his paternal（fatherly）wisdom–or at least confirm that he's the kid's dad.All he needs to do is shell our$30 for paternity testing kit（PTK）at his local drugstore–and another$120 to get the results.More than 60,000 people have purchased the PTKs since they first become available without prescriptions last years,according to Doug Fog,chief operating officer of Identigene,which makes the over-the-counter kits.More than two dozen companies sell DNA tests Directly to the public,ranging in price from a few hundred dollars to more than$2,500.Among the most popular:paternity and kinship testing,which adopted children can use to find their biological relatives and families can use to track down kids put up for adoption.DNA testing is also the latest rage among passionate genealogists—and supports businesses that offer to search for a family's geographic roots.Most tests require collecting cells by swabbing saliva in the mouth and sending it to the company for testing.All tests require a potential candidate with whom to compare DNA.But some observers are skeptical,"There is a kind of false precision being hawked by people claiming they are doing ancestry testing,"says Trey Duster,a New York University sociologist.He notes that each individual has many ancestors-numbering in the hundreds just a few centuries back.Yet most ancestry testing only considers a single lineage,either the Y chromosome inherited through men in a father's line or mitochondrial DNA,which is passed down only from mothers.This DNA can reveal genetic information about only one or two ancestors,even though,for example,just three generations back people also have six other great-grandparents or,four generations back,14 other great-great-grandparents.Critics also argue that commercial genetic testing is only as good as the reference collections to which a sample is compared.Databases used by some companies don't rely on data collected systematically but rather lump together information from different research projects.This means that a DNA database may have a lot of data from some regions and not others,so a person’s test results may differ depending on the company that processes the results.In addition,the computer programs a company uses to estimate relationships may be patented and not subject to peer review or outside evaluation.26.In paragraphs 1 and 2,the text shows PTK's___________.

A.easy availability
B.flexibility in pricing
C.successful promotion
D.popularity with households

共用题干
第二篇

DNA Fingerprinting

DNA is the genetic material found within the cell nuclei of all living things. In mammals（哺乳动物）
the strands of DNA are grouped into structures called chromosomes（染色体）.With the exception of identical
twins,the complete DNA of each individual is unique.
DNA fingerprinting is sometimes called DNA typing. It is a method of identification that compares bits
of DNA.A DAN fingerprint is constructed by first drawing out a DNA sample from body tissue or fluid such
as hair , blood，or saliva（唾液）.The sample is then segmented using enzymes（酶）,and the segments are
arranged by size.The segments are marked with probes and exposed on X-ray film,where they form a pat-
tern of black bars一the DNA fingerprint.If the DNA fingerprints produced from two different samples match,
the two samples probably came from the same person.
DNA fingerprinting was first developed as an identification technique in 1985.Originally used to detect
the presence of genetic diseases,it soon came to be used in criminal investigations and legal affairs.The first
criminal conviction based on DNA evidence in the United States occurred in 1988.In criminal investiga-
tions,DNA fingerprints derived from evidence collected at the crime scene are compared to the DNA finger-
prints of suspects.Generally,courts have accepted the reliability of DNA testing and admitted DNA test re-
sults into evidence.However,DNA fingerprinting is controversial in a number of areas:the accuracy of the
results,the cost of testing,and the possible misuse of the technique.
The accuracy of DNA fingerprinting has been challenged for several reasons. First,because DNA segments
rather than complete DNA strands are"fingerprinted";a DNA fingerprint may not be unique;large-scale
research to confirm the uniqueness of DNA fingerprinting.test results has not been conducted.In addition,
DNA fingerprinting is often done in private laboratories that may not follow uniform testing standards and
quality controls.Also,since human beings must interpret the test,human error could lead to false results.
DNA fingerprinting is expensive.Suspects who are unable to provide their own DNA to experts may not
be able to successfully defend themselves against charges based on DNA evidence.
Widespread use of DNA testing for identification purposes may lead to the establishment of a DNA
fingerprint database.

People question the reliability of DNA fingerprinting for________.
A:the subjective interpretation of test results
B:its complex procedure
C:its large scale research
D:its uniform testing standards

共用题干
第二篇

DNA Fingerprinting

DNA is the genetic material found within the cell nuclei of all living things. In mammals（哺乳动物）
the strands of DNA are grouped into structures called chromosomes（染色体）.With the exception of identical
twins,the complete DNA of each individual is unique.
DNA fingerprinting is sometimes called DNA typing. It is a method of identification that compares bits
of DNA.A DAN fingerprint is constructed by first drawing out a DNA sample from body tissue or fluid such
as hair , blood，or saliva（唾液）.The sample is then segmented using enzymes（酶）,and the segments are
arranged by size.The segments are marked with probes and exposed on X-ray film,where they form a pat-
tern of black bars一the DNA fingerprint.If the DNA fingerprints produced from two different samples match,
the two samples probably came from the same person.
DNA fingerprinting was first developed as an identification technique in 1985.Originally used to detect
the presence of genetic diseases,it soon came to be used in criminal investigations and legal affairs.The first
criminal conviction based on DNA evidence in the United States occurred in 1988.In criminal investiga-
tions,DNA fingerprints derived from evidence collected at the crime scene are compared to the DNA finger-
prints of suspects.Generally,courts have accepted the reliability of DNA testing and admitted DNA test re-
sults into evidence.However,DNA fingerprinting is controversial in a number of areas:the accuracy of the
results,the cost of testing,and the possible misuse of the technique.
The accuracy of DNA fingerprinting has been challenged for several reasons. First,because DNA segments
rather than complete DNA strands are"fingerprinted";a DNA fingerprint may not be unique;large-scale
research to confirm the uniqueness of DNA fingerprinting.test results has not been conducted.In addition,
DNA fingerprinting is often done in private laboratories that may not follow uniform testing standards and
quality controls.Also,since human beings must interpret the test,human error could lead to false results.
DNA fingerprinting is expensive.Suspects who are unable to provide their own DNA to experts may not
be able to successfully defend themselves against charges based on DNA evidence.
Widespread use of DNA testing for identification purposes may lead to the establishment of a DNA
fingerprint database.

DNA fingerprinting was first used in________.
A:criminal investigation
B:animal reproduction
C:private laboratories
D:genetic disease detection

共用题干
第二篇

DNA Fingerprinting

DNA is the genetic material found within the cell nuclei of all living things. In mammals（哺乳动物）
the strands of DNA are grouped into structures called chromosomes（染色体）.With the exception of identical
twins,the complete DNA of each individual is unique.
DNA fingerprinting is sometimes called DNA typing. It is a method of identification that compares bits
of DNA.A DAN fingerprint is constructed by first drawing out a DNA sample from body tissue or fluid such
as hair , blood，or saliva（唾液）.The sample is then segmented using enzymes（酶）,and the segments are
arranged by size.The segments are marked with probes and exposed on X-ray film,where they form a pat-
tern of black bars一the DNA fingerprint.If the DNA fingerprints produced from two different samples match,
the two samples probably came from the same person.
DNA fingerprinting was first developed as an identification technique in 1985.Originally used to detect
the presence of genetic diseases,it soon came to be used in criminal investigations and legal affairs.The first
criminal conviction based on DNA evidence in the United States occurred in 1988.In criminal investiga-
tions,DNA fingerprints derived from evidence collected at the crime scene are compared to the DNA finger-
prints of suspects.Generally,courts have accepted the reliability of DNA testing and admitted DNA test re-
sults into evidence.However,DNA fingerprinting is controversial in a number of areas:the accuracy of the
results,the cost of testing,and the possible misuse of the technique.
The accuracy of DNA fingerprinting has been challenged for several reasons. First,because DNA segments
rather than complete DNA strands are"fingerprinted";a DNA fingerprint may not be unique;large-scale
research to confirm the uniqueness of DNA fingerprinting.test results has not been conducted.In addition,
DNA fingerprinting is often done in private laboratories that may not follow uniform testing standards and
quality controls.Also,since human beings must interpret the test,human error could lead to false results.
DNA fingerprinting is expensive.Suspects who are unable to provide their own DNA to experts may not
be able to successfully defend themselves against charges based on DNA evidence.
Widespread use of DNA testing for identification purposes may lead to the establishment of a DNA
fingerprint database.

It can be inferred from Paragraph 5 that DNA fingerprinting________.
A:is costly to the police
B:could be a social issue
C:is the only way to prove innocence
D:has been a profitable business

共用题干
第二篇

Are These Food Safe to Eat?

Traditionally,in plant breeding,there are crossing varieties of the same species in ways they could cross naturally.For example,disease-resistant varieties of wheat have been crossed with highyield wheat to combine these properties.This type of natural gene exchange is safe and fairly predictable.
Genetic engineering(GE)makes it possible to exchange genes between unrelated species that cannot exchange genes with each other in a natural way.GE can involve the exchange of genes be-tween vastly different species一e.g. putting scorpion toxin genes into maize or fish antifreeze genes into tomatoes.It is possible that a scorpion toxin gene,even when it is in maize DNA,will still get the organism to produce scorpion toxin一but what other effects may it have in this alien environment? We have already realized this problem一adding human growth hormone genes to pigs certainly makes them grow一but it also gives them arthritis and makes them cross-eyed,which was entirely out of expectation.
It won't be difficult to find out,for example,that the gene for human intelligence will not have the same effect if it is inserted into cabbage DNA as it had in human DNA一but what side-effect would it have?In other words,is genetically modified(GM)food safe to eat?The answer is that no-body knows because long-term tests have not been carried out.
Those companies who want a GM product approved in the UK or USA are required to provide regulatory bodies with results of their own safety tests.Monsanto's soya beans were apparently fed to fish for 10 weeks before being approved.There was no requirement for independent testing,for longterm testing,for testing on humans or testing for specific dangers to children or allergic people.
The present opinion of the British Government is that"There is no evidence of long-term dangers from GM foods."In the US,the American Food and Drug Administration is now being prosecuted for covering up research that suggested possible risks from GM foods.

Which statement about GM product is true according to the passage?
A:Adding human growth hormone genes to pigs does not make them grow.
B:The American Food and Drug Administration is now doing a research that suggested possible risks from GM foods.
C:The gene for human intelligence will not have the same effect if it is inserted into cabbage DNA as it had in human DNA.
D: There has been requirement for independent testing,for long-term testing,for testing on humans or testing for specific dangers to children or allergic people.

共用题干
第一篇

DNA Testing

DNA testing reveals the genes of each individual person.Since the early twentieth century scientists
have known that all human characteristics are contained in a person's genes and are passed from parents to
children.Genes work as a chemical instruction manual for each part and each function of the body.Their
basic chemical element is called DNA,a copy of which can be found in every cell. The existence of genes
and the chemical structure of DNA were understood by the mid-1900s,but scientists have only recently been
able to identify a person from just a drop of blood or a single hair.
One of the most important uses of DNA testing is in criminal investigation.The very first use of DNA
testing in a criminal case was in 1985 in Great Britain,when a man confessed to killing a young woman in
the English countryside.Because police had found samples of the killer's DNA at the scene of the crime,a
biologist suggested that it might be possible to compare that DNA to some from the confessor's blood.To
everyone's surprise,the tests showed that he was not the killer. Nor was he guilty of a similar murder that
had happened some time earlier. At that point he admitted that he had confessed to the crimes out of fear
and police pressure.The police then asked 5,000 local men for samples of their blood,and DNA testing
revealed that one of them was the real murderer,so the first man was set free.
In 1992,two law professors,Peter Neufeld and Bany Scheck,decided to use DNA evidence to help set free
such mistakenly convicted prisoners.With the help of their students.they created a not-for-profit organization
called the Innocence Project. Most of their clients are poor men,many from racial and ethnic minorities.In
fact,studies have shown that U. S. judges and juries are often influenced by racial and ethnic background,and
that people from minority groups are more likely to be convicted. Some of these men had been sentenced to
death,a form of punishment used in thirty eight states out of fifty(as of 2006).For most of these prisoners,their
only hope was another trial in which DNA testing could be used to prove their innocence.
Between 1992 and 2006,the Innocence Project helped free 100 men.Some of these prisoners had been
in jail for ten,twenty years or more for crimes they did not commit.However,the goal of the Innocence
Project is not simply to set free those who are wrongfully in jail.They also hope to bring about real changes
in the criminal justice system.
Illinois in the late 1990s,a group of journalism students at Northwestern University were able to bring
about such a change in that state.They began investigating some Illinois prisoners who claimed to be inno-
cent. Through DNA testing,the students were able to prove that in fact the prisoners were not guilty of the
crimes they had been accused of. Thirteen of these men were set free,and in 2000,Governor Ryan of
Illinois decided to stop carrying out death sentences until further study could be made of the prisoners'
cases。
The use of DNA in criminal cases is still being debated around the world.Some fear that governments
will one day keep records of everyone'sDNA,which could put limits on the privacy and freedom of citizens.
Other people mistrust the science of DNA testing and think that lawyers use it to get their clients free whether
or not they are guilty.But for those whose innocence has been proven and who are now free men,DNA
testing has meant nothing less than a return to life.And with the careful use of DNA testing,no innocent
person should ever be convicted again.

DNA testing was first used in a criminal case by___________.
A:a lawyer in New York
B:students in Illinois
C:doctors in the United States
D:police in Great Britain