问题 选择题

早春播种后,用“地膜覆盖”的方法促进早出苗,其原理是

A.保湿保温、有利萌发

B.种子萌发需要避光

C.防止鸟类取食种子

D.防止风沙

答案

答案:A

题目分析:种子的萌发的外界条件为一定的水分、适宜的温度和充足的空气,自身条件是有完整而有活力的胚及胚发育所需的营养物质,而植物的生长需要一定的水分、适宜的温度,在早春季节往往这两方面不足,“地膜覆盖”的方法可以保湿、保温有利于种子萌发,使蔬菜破季上市。

点评:此题为基础题,解答此题的关键是掌握种子的萌发的外界条件只有水分、温度、空气,不包括光照、风沙等。

阅读理解

Alexis was hot and tired. With rage in her voice she shouted, "Pull me up!I give up, I hate this. This is stupid!" It was at that moment when Jason, the adviser on the trip, looked at me and said, "Ed, I'm going to go down and talk with her." I then shouted down to Alexis, "Hold on! You can do this. We know you can!"

Jason grasped another rope, put his climbing harness(系带)on and began to repel down the cliff. Within moments Jason was beside Alexis. She had her cheek directly against the face of the rock with her feet barely resting on a small piece of the cliff that jetted outward. Jason said to Alexis, "I know that you have been on this cliff now for what seems like a long time. Your feet and fingers are cramping(痉挛)up and your forearms feel as though they are on fire. But , Alexis, you are strong, look how far up you are already. You have taken one of the more difficult paths up the cliff. Look Alexis, look at the path you have taken."

At that moment, Alexis moved her cheek away from the rock face and looked down. The bright white chalk she used on her hands to give her a better hold, showed the path where her tired hands had moved her upward on the cliff. Jason was right. Alexis had taken the hardest way up the cliff. Jason then looked straight into Alexis' eyes and in a calm voice he said, "You are not alone out here, there are people who care about you, who want to help you and see you succeed. We are going to do this together. Are you ready?" Slowly she shook her head yes and took a deep breath.

小题1:Jason went down the cliff because _________.

A.Alexis took a wrong path

B.Alexis was trapped in rocks

C.Alexis didn't believe in herself

D.Alexis' forearms were badly hurt小题2:We can infer from the passage that ________.

A.Alexis was finally pulled up by Ed

B.Alexis regretted having taken the wrong path up the cliff

C.Alexis was immediately sent to hospital after she was pulled up

D.Alexis successfully rock climbed小题3:The underlined word "hot" in the story means _________.

A.disappointed

B.angry

C.uncomfortable

D.running a high body temperature小题4:Alexis would probably become _________.

A.more strong-minded

B.easier to give up

C.poorer in health

D.less interested in rock climbing

单项选择题