A:在使用苏丹Ⅲ鉴定脂肪的实验中,酒精的作用是洗去实验材料上的浮色
B:无水酒精在绿叶中色素的提取和分离实验中起到提取色素的作用
C:探究酵母菌细胞呼吸的方式实验中,用酸性条件下的重铬酸钾溶液检验酒精会变成灰绿色
D:在观察DNA和RNA分布的实验中,可用酒精来改变细胞膜通透性,加速染色剂进入细胞
—I have lost my e-dictionary—_________.
Hi,I'm Betty.I come from Sydney.I'm a student.I eat breakfast at home.And then I go to school at 8:30.Classes start at 9:00.After school,I usually play sports with my friends.On the weekend,I often take a dancing class and play music.Sometimes I watch TV and read books.
My favourite season is summer.Because Christmas is in summer.In Australia,summer is from December to February the next year.I usually go to the beach and swim on Christmas Day.What about you?