问题
单项选择题
视锥细胞在何处最密集
A．视网膜的外周
B．中央凹
C．视网膜中心
D．视盘
E．视盘周围
答案
参考答案：B
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视锥细胞在何处最密集
A．视网膜的外周
B．中央凹
C．视网膜中心
D．视盘
E．视盘周围
参考答案：B
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| In the depths of my memory, many things I did with my father still live. These things have come to represent, in fact, what I call 1 and love. I don't remember my father ever getting into a swimming pool  . But he did 2 the water. Any kindof 3 ride seemed to give pleasure. 4 he loved to fish; sometimes he took me along. But I never really liked being on the water the way my father did. I liked being 5 the water, moving through it, 6 it all around me. I was not a strong 7 , or one who learned to swim early, for I had my 8  . but I loved being in the swimming pool close to my father's office and 9 those summer days with my father, who 10 come by on a break. I needed him to see what I could do. My father would stand there in his suit, the 11 person not in swimsuit. After swimming, I would go 12 his office and sit on the wooden chair in front of his big desk, where he let me 13 anything I found in his top desk drawer. Sometimes, if I was left alone at his desk 14 he worked in the lab, an assistant or a student might come in and tell me perhaps I shouldn't be playing with his 15 . but my father always 16 and said easily, "Oh, no, it's 17 ." Sometimes he handed me coins and told me to get 18 an ice cream… | ||||
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