用for或是since 填空(1)Mr. Brown has had his TV ______ 15 years.(2)I’ve taken driving lessons _______last month.(3)My sister has had her cell phone ______a month .(4)My friends haven’t visited me ______few days ago.(5)We haven’t used our car _____ a long time .
4.精子在体内主要储存在
A. 输精管和附睾
B. 睾丸
C. 前列腺
D. 精囊腺
E. 尿道球腺
13.关于睾丸的生精功能,叙述正确的是
A. 支持细胞生成精子
B. 原始的生精细胞为精原细胞
C. 支持细胞分泌雄激素
D. 精子生成的适宜温度37度
E. X线照射可促进生精作用