题目

正常情况下，将成熟的花粉粒离体条件下培养成单倍体植株幼苗时，细胞内不可能出现的是A．染色单体形成     B．染色体联会 C．DNA复制       D．染色体复制 答案：B根据短文内容回答问题。Ben is very happy today. He goes to the park at eight thirty. He plays football with friends at ten. At eleven forty-five, he goes to the restaurant with his parents. Ben goes to the movie theater at five o’clock, at six thirty, he goes home.1.Yes or No.( ) (1) Ben goes to the park at six thirty.( ) (2) Ben goes to the restaurant with his grandma.( ) (3) At five o’clock, Ben goes to the movie theater.2.Answer the questions.(1) What time does Ben play football?___________________________________ .(2) Is Ben happy today?___________________________________ .