题目

下列关于“细胞大小与物质运输的关系”实验的叙述正确的是( )A. 细胞体积越大，相对表面积越大，物质运输的效率越低B. 细胞核所控制的细胞大小与细胞核的大小星一定比例C. NaOH在琼脂块内扩散的速率代表物质运输的效率D. NaOH在不同大小的琼脂块内扩散的速率不同 答案：【答案】B【解析】探究细胞表面积与体积之比，与物质运输速率之间的关系：体积越大，相对表面积越小，物质运输的效率越低；实验中测量不同大小的琼脂块上NaOH扩散的深度相同；实验所用的琼脂小块上含有酚酞，NaOH和酚酞相遇，呈紫红色。细胞体积越大，相对表面积越小，则物质运输的效率越低完型填空（10分）One day. A farmer was walking along a road with his son Thomas. The father said, “Look! There’s a horseshoe   31  the ground. Pick it up and put it in your bag.” Thomas said, “It wastes my time. ” His father said   32  but he picked it up himself. When they got to a nearby town, they had a rest. There the farmer   33  the horseshoe and with the money he bought some strawberries.The father and the son went on walking. The sun was well up in the   34 . They soon drank up their water, and there wasn’t a house or even a tree for them to   35 . Thomas felt too   36  to walk on. At this time, his father gave Thomas a strawberry   37  he quickly ate it. After a while, his father gave him    38  strawberry and once again, his son lost no time in putting it in his mouth.And so they   39 . The old farmer gave the strawberries and the son ate them. When Thomas had eaten up all the strawberries, his father said to him, “My dear son, if you picked up that horseshoe, you would have your own strawberries   40 . Always remember the lesson: If you don’t worry about the little things, you’ll find difficult to do the great things.”【小题1】A．underB．onC．forD．to【小题2】A．everyoneB．anythingC．nothingD．someone【小题3】A．threw B．soldC．foundD．bought[来源:学*科*网]【小题4】A．skyB．mountainC．riverD．tree【小题5】A．have a look B．have a tryC．have a restD．have a picture【小题6】A．excitedB．coldC．fullD．thirsty【小题7】A．andB．thoughC．orD．because【小题8】A．the othersB．anotherC．othersD．other one【小题9】A．turned upB．came downC．went onD．got over【小题10】A．to drinkB．to rideC．to useD．to eat