问题 问答题 简答题

视网膜上有哪些重要结构标志?

答案

参考答案:

视网膜是一层透明的膜,位于脉络膜内侧,在视网膜后极部有一中央无血管的凹陷区解剖上称中心凹,临床上称为黄斑,其中央有一小凹,是视网膜上视觉最敏锐的部位。黄斑区色素上皮细胞含有较多色素,中心凹处可见反光点,称为中心凹反射。距黄斑鼻侧约3mm处有一约1.5mm×1.75mm境界清楚的,橙红色的圆形盘状结构,称为视盘(opticdisc)又称为视 * * (opticpapilla),是视网膜上视觉神经纤维汇集组成视神经,向视中枢传递穿出眼球的部位。视盘中央有一小凹陷区称视杯或杯凹(opticcup)。视盘上有视网膜中央动静脉通过,并分布于视网膜,分为颞上、下、鼻上下分支。

完形填空

第二部分:语言知识与应用(共两节,满分25分)

第一节:完型填空(共10小题,每小题1分,共10分)

阅读下面短文,掌握其大意,然后从21 - 30各题所给的四个选项中,选出最佳选项。

Small moments sometimes last a very long time. And a few words---though they mean ___21___ at the time to the people who say them --- can have great power.

I recently heard a story from Malcolm Dalkoff, who has been a professional ___22___ for the last twenty-four years, mostly in advertising.

As a boy, Dalkoff was terribly shy and ___23___. He had few friends and no self-confidence. Then one day, his high school English teacher, Ruth Brauch, asked the class to write their own chapter that would ___24___ the last chapter of the novel since they had been reading To Kill a Mockingbird. Dalkoff wrote his chapter and turned it in. Today he cannot recall anything special about the chapter he wrote, or what ___25___ Mrs. Brauch gave him. ___26___, what he does remember is the four words in the paper: “This is good writing.” Thanks to the four words, his life has been ___27___ greatly.

“ Until I read those words, I had no idea of who I was or what I was or what I was going to be,” he said, “ After reading her ___28___, I went home and wrote a short story, ___29___ I had always dreamed of doing but never believed I could do.”

Over the rest of that year in school, he wrote many short stories, and always brought them to Mrs. Brauch for instruction. “She was ___30___, helpful and honest. She was just what I needed,” Dalkoff said.

21.     A. much                     B. little                      C. well                       D. ill

22.     A. report            B. designer                C. writer                    D. teacher

23.     A. weak                     B. independent            C. troublesome            D. helpless

24.     A. follow                   B. change                   C. connect                  D. explain

25.     A. help                       B. encouragement        C. grade                     D. words

26.     A. Therefore               B. However                C. Meanwhile             D. Besides

27.     A. improved               B. developed               C. changed                 D. enriched

28.     A. chapter                  B. novel                     C. note                       D. explanation

29.     A. everything              B. something              C. nothing                  D. anything

30.     A. encouraging           B. careful                   C. strict                      D. effective

单项选择题 A1/A2型题