问题 解答题

联系农业生产的实际,列举一些促进生物体由小长大的生产措施.

答案

水是组成植物细胞的重要成分,即使干燥的种子里也含有水分;光合作用吸收二氧化碳和水,因此水是植物进行光合作用的重要原料,植物的生长需要多种无机盐,无机盐必须溶解在水中植物才能吸收利用.植物需要量最大的无机盐是含氮、含磷、含钾的无机盐.氮肥作用:促使作物的茎,叶生长茂盛,叶色浓绿;钾肥的作用:促使作物生长健壮,茎秆粗硬,增强病虫害和倒伏的抵抗能力;促进糖分和淀粉的生成;磷肥的作用:促使作物根系发达,增强抗寒抗旱能力;促进作物提早成熟,穗粒增多,籽粒饱满.强植物光合作用的强度,降低呼吸作用的强度,可以使有机物积累的量增加,从而提高产量.实际的农业生产上,往往通过合理密植、间作套种等措施,提高作物的光合作用效率,从而达到增产的目的.

故答案为:植物生长需要养分,一、正确、合理施用化肥已经成为农作物增产的有力措施.二、要适时适量向农作物浇水.三、通过合理密植、间作套种的措施

阅读理解

Grown-ups are often surprised by how well they remember something they learned as children but have never practiced ever since. A man who has not had a chance to go swimming for years can still swim as well as ever when he gets back in the water. He can get on a bicycle after many years and still ride away. He can play catch and hit a ball as well as his son. A mother who has not thought about the words for years can teach her daughter the poem that begins "Twinkle, twinkle, little star" or remember the story of Cinderella or Goldilocks and the Three Bears.

One explanation is the law of overlearning, which can be stated as follows: Once we have learned something, additional learning trials(尝试) increase the length of time we will remember it.

In childhood we usually continue to practice such skills as swimming, bicycle riding, and playing baseball long after we have learned them. We continue to listen to and remind ourselves of words such as "Twinkle, twinkle, little star" and childhood tales such as Cinderella and Goldilocks. We not only learn but overlearn.

The multiplication tables(乘法口诀表) are an exception to the general rule that we forget rather quickly the things that we learn in school, because they are another of the things we overlearn in childhood.

The law of overlearning explains why cramming(突击学习)for an examination, though it may result in a passing grade, is not a satisfactory way to learn a college course. By cramming, a student may learn the subject well enough to get by on the examination, but he is likely soon to forget almost everything he learned. A little overlearning, on the other hand, is really necessary for one's future development.

小题1:What is the main idea of paragraph 1?

A.People remember well what they learned in childhood.

B.Children have a better memory than grown-ups.

C.Poem reading is a good way to learn words.

D.Stories for children are easy to remember.小题2:The author explains the law of overlearning by_________.

A.presenting research findings

B.setting down general rules

C.making a comparison

D.using examples小题3:According to the author, being able to use multiplication tables is_______.

A.a result of overlearning

B.a special case of cramming

C.a skill to deal with math problems

D.a basic step towards advanced studies小题4:What is the author's opinion on cramming?

A.It leads to failure in college exams.

B.It's helpful only in a limited way.

C.It's possible to result in poor memory.

D.It increases students' learning interest.

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