不经过受精作用就能产生新个体来延续后代的方式包括()。
A.单性结实
B.无融合生殖
C.营养繁殖
D.B和C
参考答案:D
The private automobile has long played an important role in the US. In fact, it has become 小题1:___necessary and important part of the American life. In 1986, sixty-nine percent of American families owned 小题2:__least one car, and thirty-eight percent had 小题3:___than one. With the convenience of rapid transportation, workers don’t have to live near their workplace. This has encouraged the growth of the cities, 小题4:___it has also led to traffic problems.
For farm families the automobile is very helpful. It has made 小题5:___ possible for them to travel to town very often for business and for pleasure.
Family life has been affected in 小题6:___ways. The car helps to keep families together. However, when teenage children use the car, their parents can’t keep an eye on them. There is a great danger 小题7:____the driver has been drinking alcohol or taking drugs or breaking 小题8:_____ traffic laws.
Cars mean very much to Americans.
急性颅内压增高已出现脑疝症状时首先选用
A.20%甘露醇B.地塞米松C.50%葡萄糖D.醋氮酰胺E.腰穿降颅压