题目

下列有关叙述，正确的是A. 下丘脑有体温调节中枢，也有感觉体温变化的功能B. 小肠上皮细胞吸收溶质发生障碍时，可导致小肠吸水减少C. 苹果树开花后，喷施适宜浓度的乙烯利可防止果实脱落D. 用生长素类似物处理二倍体番茄幼苗，可得到多倍体番茄 答案：【答案】B【解析】A、下丘脑是体温调节中枢，大脑皮层是温度感觉中枢，A错误B、由于水的吸收属于自由扩散，靠浓度差维持，故小肠上皮细胞吸收溶质发生障碍时，可导致小肠吸水减少，B正确；C、脱落酸能够促进果实的衰老和脱落，C错误D. 生长素类似不会导致染色体数目加倍，故D错误。单词拼写1.It’s three k___________from my home to school.So I usually take the bus to school.2.IT takes us twenty m___________ to walk to the park.3.In our school a small n_____________ of students go to school by bus.4.Li lei takes the _________________（地铁）to school every day.5.His father often goes to Shanghai by __________________(飞机).