题干

下列关于基因的叙述中,正确的是

A:每一个DNA片段都是一个基因

B:每一个基因都控制着一定的性状

C:有多少基因就控制着多少遗传性状

D:基因控制的性状都能在后代表现出来

上一题 下一题 0.0难度 选择题 更新时间:2015-09-23 05:16:57

答案(点此获取答案解析)

B

同类题5

     A 14-year-old British student is packing for the next day of school: textbooks, notebooks, pens, 250 grams of flour, an egg and some cooking oil. Wait, what? It's not a joke.
      From September, cookery will be a compulsory (必修的) course for kids aged 7-14 in the UK.Primary school students will learn how to put things together and make simple, healthy food.
     At high school, students will then master a number of different meals. They will also learn some cooking skills including baking.
Britain is sometimes known as a country with bad food and unhealthy eating habits. These new courses are part of the country’s effort to bring healthy food back onto the table.
     “One in four British families no longer has a table that everyone can eat around. One out of every two meals we eat is eaten alone. Only four out of ten of us enjoy eating meals with our children,” British writer Joanna Blythman wrote in her book Bad Food Britain: How A Nation Ruined Its Appetite (食欲) in 2006.
     Instead, ready meals have become the first choice for many British kids, because their parents are often too busy to cook a proper meal.
The Department for Education hopes that the cookery courses can introduce children to good food and reduce childhood obesity.
“It's important that children can develop an interest and understanding of good food,” said a spokesman for the department.
    “We want to encourage them to develop a love of food and cooking that will stay with them as they grow up.