问题
选择题
下列关于物质跨膜运输的叙述正确的是[ ]
A．植物细胞积累K+不需要消耗能量
B．除去细胞膜上的蛋白质会影响细胞对离子的吸收
C．小分子物质和离子都是通过自由扩散进入细胞
D．葡萄糖等较大的分子只能通过主动运输进入细胞
答案
答案：B
搜题请搜索小程序“爱下问搜题”
下列关于物质跨膜运输的叙述正确的是[ ]
A．植物细胞积累K+不需要消耗能量
B．除去细胞膜上的蛋白质会影响细胞对离子的吸收
C．小分子物质和离子都是通过自由扩散进入细胞
D．葡萄糖等较大的分子只能通过主动运输进入细胞
答案：B
In real life, robots are mainly used in factories. They do many different jobs. Usually these jobs are too , difficult or boring for humans. Robots also help disabled people and people who cannot look after . For example, scientists are making a robot to help people. Now many of them have a dog to help them. The dog is called a guide dog. In the future, guide dogs might be robot dogs. One robot dog is called Meldog. It has wheels. It usually “walks” its owner. It is very clever. It knows the speed of its owner’s walk. Meldog talks to its owner by . The owner wears a special belt. This belt instructions to the owner from Meldog such as “Stop here”, “Turn left” and “Turn right”. In the United States, another of robot helps disabled workers. This robot, called Kilroy, helps disabled computer operators. The robot the sound of its owner’s voice. It follows instructions such as “Turn the page” and “Make a cup of coffee”. Robots are also used in American . They can do simple jobs. For example, they shave (刮脸) patients and brush their teeth and take meals from the kitchen to patients’ rooms. It never gets lost this robot has a map of the hospital in its computer memory.
|