题干

下列关于细胞膜的流动性和选择透过性的叙述,不正确的是(    )

A:流动性的基础是组成细胞膜的磷脂分子和蛋白质分子大多是流动的

B:选择透过性的基础是细胞膜上的载体蛋白和磷脂分子具有特异性

C:细胞的胞吞和胞吐体现了细胞膜的流动性

D:钾离子通过主动运输的形式进入细胞体现了细胞膜的选择透过性

上一题 下一题 0.0难度 选择题 更新时间:2017-12-23 11:35:36

答案(点此获取答案解析)

B

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    You never played the video dance game? Now such games are used to help lose weight!

    Like many other teenage boys, Jones loves sports. But at 5 feet, 175 pounds, he found his weight in trouble. His doctor wanted him to lose 50 pounds so that he may be a good football game player by the end of the summer.

    Jones chose the popular Dance Revolution video game at home to increase his activity. He had lost about 10 pounds by changing his diet. Now, after two weeks' playing the game, he has lost another 10!

    A health study is being done by an insurance company. The company hopes that the game will lead to better health and lower costs. “Obesity claims last year cost us $ 77 million. We have to cut those costs,” said a member of the insurance group. The company provides a game console (游戏主机), a dance mat and software for the six-month, $ 60,000 study.

    The study is more than a commercial thing of an insurance company. It is widely supported by physical education and health professionals.

    In West Virginia, 43% of the nearly 6,000 children examined for heart disease risk were considered over-weighted; more than 25% were too fat. “We are in a crisis of childhood obesity not only in West Virginia but in America,” said a researcher.

    Researchers are now looking at the potential for improving effects by using the game. A teacher in West Virginia has been using the video games in her classes since last fall. She reported that the game does improve heart health as well as eye-hand coordination (协调能力), and her students take the video game as a great alternative to jumping rope or ball games.

    The US Education Department is putting the game in 20 schools to control childhood obesity. Well, are you going to try such to dance away your extra weight?