问题 填空题

据调查统计,山东省初中学生视力不良(主要是近视)检出率为62%,比全国高出20多个百分点.这引起了社会各界对学生用眼卫生的高度关注.右图是眼球结构示意图,请据图回答:

(1)通常被称为“黑眼珠”的结构是____________.

(2)检查视力时,视力表上的“b”落在被检查者______视网膜上的图象是“______”.

(3)若沉溺于上网或长时间近距离看书写字、看电视,容易使____________的调节负担过重不能恢复原状,致使远处物体折射所形成的物像落在了视网膜的______,形成近视.近视眼可通过佩戴如右图______透镜(填序号)加以矫正.

答案

(1)眼球的结构中被称为“黑眼珠”的结构是图中的9虹膜,因为它不但能够调节瞳孔的大小,里面还有色素,这就是东方人“黑眼球”和西方人的“蓝眼睛”的原因;

(2)视觉的形成过程是:外界物体反射的光线,经过1角膜、房水,由2瞳孔进入眼球内部,经过8晶状体和10玻璃体的折射作用,形成一个倒置的物像.5视网膜上的感光细胞接受物像的刺激产生神经冲动,然后通过6视神经传到大脑皮层的视觉中枢,形成视觉.

(3)若不注意用眼卫生,如长时间近距离看书,就会使8晶状体的曲度过度变凸,甚至眼球的前后径变长,远处物体所形成的物像落到视网膜的前方,从而看不清远处的物体,形成近视.可以戴凹透镜来纠正.

故答案为:(1)9虹膜;(2)5;倒像;(3)8晶状体;前方;A.

单项选择题
阅读理解

阅读理解。

      Have you ever been to a wedding and simply loved the bride's bouquet (花束)? More than

likely some part of it was the Hawaiian Wedding Plant. This exotic(外国的) houseplant can be

enjoyed by anyone, not just brides. With a little proper attention and carefully planning on location,

this foreign houseplant, native to Madagascar, can be brought into the home where it can become

an interesting focus.

     Caring for the Hawaiian Wedding Plant is not much different than that of any other houseplants

being in your home. The basic requirements of water, soil, light and a good fertilizer are required for

this beautiful, exotic houseplant. The only difference between this type of houseplant and others is the

amount of the basic requirements that it needs to survive and perform beautifully. During the growing

season, it requires its soil moist(潮湿的), but when winter rolls around, it needs its soil to be kept drier.

     Hawaiian Wedding Plants should also be potted in welldrained soil and placed in a location that

receives full sun to bright shade. Mist the foliage(叶子) daily and feed this plant every two to three

weeks with a slowrelease fertilizer for acidloving plants. Prune(修剪) in early spring, even as early as

February.

     The most special feature of it is its long lasting blooms combined with fabulous fragrance(奇妙的

芳香). The Hawaiian Wedding Plant blooms the heaviest in the spring months, but has been known

to bloom in any warm months, so do not be surprised to find blooms most anytime of the year except

maybe in the dead of winter. When they do bloom, seedpods(豆荚) will often form and should

be allowed to dry while on the vine(藤). Do not pick these seedpods too early and expect to use the

seeds for propagation(繁殖). After the seedpods have been allowed to dry on the vine, the seeds can

be planted in welldraining soil and kept moist until new Hawaiian Wedding Plants begin to grow.

     Everyone can enjoy the Hawaiian Wedding Plant, no matter what of green thumb the gardener may

be lucky enough to have. With a little attention, this beautiful, fragrant flowering exotic houseplant will be

enjoyable for many years to come, not just when attending a wedding.

1. Why does the author mention wedding and bouquet in the first paragraph? 

A. To introduce a Hawaiian wedding.

B. To attract the readers' interest.

C. To show the beauty of the flower.

D. To teach the readers to choose proper bouquets.

2. The Hawaiian Wedding Plant comes from ________. 

A. Hawaii                            

B. China

C. Madagascar                        

D. Alaska

3. Which of the following are the growing conditions of Hawaiian Wedding Plant?

a. Wet soil.    

b. Lots of fertilizer.  

c. Proper sunshine.    

d. Much room.

A. a, c                                  

B.  a, b

C. b, c                                  

D. a, d

4. What does the underlined phrase "in the dead of winter" in Paragraph 4 probably mean?

A. At the end of winter.                                

B. At the beginning of winter.

C. In the whole winter.                                

D. In the coldest part of winter.