题目

如图甲、乙表示小肠绒毛上皮细胞中的细胞膜对不同物质的转运(每种物质转运的方向由箭头表明，黑点的数量代表每种物质的浓度)，下列叙述正确的是( ) A．a物质可能是氧气，b物质可能是葡萄糖 B．a物质可能是水，b物质可能是甘油 C．a物质可能是胆固醇，b物质可能是氧气 D．a物质可能是葡萄糖，b物质可能是氨基酸   A.compared B. effect C. course D. effort E. improveSeveral studies in the past few years have shown that music lessons can have a good 1. on kids’ brain.The longer a student learns it, the more greatly he will2. . As little as four months of music lessons can lead to progress during brain development. The study followed a few four to six year old music learners over the 3. of a year, measuring changes in each kid’s brain. When the scientists 4. the music learner with a group of non-music learners, they found music students’ brains were developing differently.