家兔的心脏与哪一种动物的心脏结构基本相同？（ ）
A．鲤鱼
B．青蛙
C．蝗虫
D．家鸽
A、鱼类终生生活在海水或淡水中，大都具有适于游泳的体形和鳍．用鳃呼吸，出现了能跳动的心脏分为一心房和一心室，家兔是二心房，二心室，体温恒定，故不符合题意．
B、青蛙的心脏结构是二心房一心室，与家兔的心脏不相同，故不符合题意．
C、蝗虫是节肢动物门的代表，它的心脏结构不如家兔哺乳动物的复杂，故不符合题意．
D、家鸽的心脏结构也是二心房、二心室四个腔，和家兔的心脏结构基本相同，符合题意．
故选；D
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| Long ago, in a small village of Wakefield lived two farmers, Harry and Peter. Harry was very hard-working while Peter was l . Every day Harry got up early and came home late, but Peter walked around for fun. One summer, there was no 2 and the crops (庄稼) were dying. Harry thought, "I must do something to save these crops, or they shall die. " With this 3_ in mind, he went out to find a river so that he could dig a canal (沟渠) to his field. He walked on and on, feeling tired and thirsty. After a 4 search, he found a river full of blue water. He was very happy. He started digging a canal to his field. 5_ it was noon, his wife sent their daughter to bring Harry home 6 lunch. But Harry did not go. He did not want to leave his work unfinished. He completed his work 7_ at night. He was very satisfied. He went home, had a good meal and _8 into a sound sleep. Peter did the same. But he was not at all determined (有决心的). He also 9 digging a canal to his field but he didn't have his work completed. His field did not get 10 water and all his crops died. Harry's field would be watered when needed. He had a good harvest because of his hard work. | ||||
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