在真核生物中，每一物种都有其特定的染色体数，牛有（）条染色体_爱下问搜题

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问题填空题

在真核生物中，每一物种都有其特定的染色体数，牛有（）条染色体。

答案

参考答案：60

完形填空

Signs can sometimes be seen at the entrance of a house, expressing that a tramp（流浪汉） has passed. This special sign-language is frequently 36 by tramps to inform their 37 whether the host of a certain house is friendly or unfriendly, and to 38 them the trouble of making unnecessary calls.
Quite 39 one day, I came across a real tramp. He was such a rare sight these days that I stood some distance away and watched him. He was dressed just as a tramp should be 40 , old worn trousers, and a jacket many sizes too big for him. On his head there was a battered old hat and his boots were so old and worn; they were almost coming into 41 . But the man himself looked cheerful as if he had not been a 42 in the world. He rubbed his nose with his forefinger, 43 a funny turn, laid a small parcel by the front gate, and began 44 a sign made by a former caller. Although the sign was meaningless to me, it must have been 45 , for the tramp’s face lit up with 46 . He entered the front gate confidently and rang the bell. When the door opened, I saw him 47 his hat but couldn’t hear his words. The 48 was very short indeed, for no sooner had he spoken a few words than the door closed fiercely in his face. I felt 49 for him as he walked 50 out of the house, But just as quickly, his face lit up again and he moved quickly towards the gate. There he stopped, looked at the sign, and 51 his head seriously as if he had made a bad mistake. 52 deeply into his pockets, he produced a piece of chalk, rubbed out the 53 sign and made a new one in its place. He stared at it for a moment smiling to himself, then gathered his 54 , pushed back his hat and began walking towards the next house at an unhurried 55 , whistling as he went along.

B．satisfaction

D．disappointment

A．conversation

B．introduction

单项选择题案例分析题

下图为某季节我国东部沿海高空等压面示意图。据此回答下列各题。

此季节，图中所示大陆上的等温线（）①向高纬凸出②向低纬凸出③向北凸出④向南凸出

A、①③

B、②④

C、①④

D、②③