[单项选择]Passage Five Modern humans emerged some 250,000 years ago, yet agriculture is a fairly recent invention, only about 10,000 years old. Many crop plants are rather new additions to our diet: broccoli (a flowering mutant of kale) is thought to be only 500 years old. Most innovation is far more recent still. Although Austrian monk Gregor Mendel’s pea plant experiments quietly laid the basic foundations of genetics in the mid-19th century, his work was rediscovered and applied to crop breeding only at the beginning of the 20th century. Further advances have steadily accumulated. The 1940s saw the identification of DNA as genetic material and the adoption, by commercial breeders, of genetic modification - typically by applying chemicals or radiation to DNA to try to make plants with advantageous characteristics. The modifications ultimately led to the green revolution of the 1960s and 1970s, during which time global wheat yields tripled. The 1980s and 1990s saw the commercial ado
A. Broccoli was first bred by Mendel.
B. Broccoli wasn’t considered edible until 500 years ago.
C. Mendel’s work was considered most important in the history of genetics.
D. Mendel’s study found its major application some 100 years ago.

更多"Passage Five Modern humans em"的相关试题:

[单项选择]Passage Five Modern humans emerged some 250,000 years ago, yet agriculture is a fairly recent invention, only about 10,000 years old. Many crop plants are rather new additions to our diet: broccoli (a flowering mutant of kale) is thought to be only 500 years old. Most innovation is far more recent still. Although Austrian monk Gregor Mendel’s pea plant experiments quietly laid the basic foundations of genetics in the mid-19th century, his work was rediscovered and applied to crop breeding only at the beginning of the 20th century. Further advances have steadily accumulated. The 1940s saw the identification of DNA as genetic material and the adoption, by commercial breeders, of genetic modification - typically by applying chemicals or radiation to DNA to try to make plants with advantageous characteristics. The modifications ultimately led to the green revolution of the 1960s and 1970s, during which time global wheat yields tripled. The 1980s and 1990s saw the commercial ado
A. Sharp rise in worldwide wheat production.
B. Extensive use of organic fertilizer.
C. Large-scale adoption of genetic modification.
D. Commercial success of genetically modified seeds.

查看答案

[填空题]The first modern humans were a group of hunter-gatherers who came to Britain because the melting ice makes their residence uninhabitable.

查看答案

[单项选择]Passage Five

Some 23 million additional U.S. residents are expected to become more regular users of the U.S. health care system in the next several years, thanks to the passage of health care reform.Digitizing medical data has been promoted as one way to help the already burdened system manage the surge in patients. But putting people’s health information in databases and online is going to do more than simply reduce redundancies. It is already shifting the very way we seek and receive health care.
"The social dynamics of care are changing," says John Gomez, vice president of Eclipsys, a medical information technology company. Most patients might not yet be willing to share their latest CT scan images over Facebook, he notes, but many parents post their babies’ ultrasound images, and countless patients nowadays use social networking sites t
A. The Future of Your Medical Data.
B. Challenges Against Doctors and Hospitals.
C. Benefits of the U. S. Health Care Reform.
D. How to Access and Share Your Health Information.

查看答案

[填空题]Paragraph Five Some people worry about the violence in TV programs and their effect on young people. Others consider that these same programs are an opportunity for us to release our stronger emotion, our feelings of anger or anxiety. Most people would agree though, that extreme violence should be kept away from children.

查看答案

[单项选择]Passage Five

At some time around 2300BC, give or take a century or two, a large number of the major civilizations of the world collapsed, in Mesopotamia, Egypt, Israel, Anatolia, and Greece, as well as in Afghanistan and China. All of them the first urban civilizations fell into rain at more or less the same time. A thousand years later, around 1200BC, many of the civilizations of the same regions again collapsed at about the same time.
The reasons for these widespread and apparently simultaneous disasters which coincided with changes to cultures and societies elsewhere, such as in Britain, have long been a fascinating mystery. Traditional explanations included warfare, famine, and more recently systems collapse, but the apparent absence of direct archaeological or written evidence for causes, as opposed to effects, has led many archaeologi
A. it occurred simultaneously.
B. it occurred at a time similar to noticeable cultural and social changes
C. there are no written records.
D. all of the above.

查看答案

我来回答:

提交