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问题 实验题

请结合右图分析回答下列有关鸟的生殖和发育的问题：

（1）诗句“谁家春燕啄春泥”描写了燕子繁殖行为中的         行为。

（2）在下图所示鸡卵结构中，将来发育成雏鸡的是［  ］       ；为胚胎发育提供营养的是［  ］         和［  ］         ，为胚胎发育提供氧气的结构是［  ］        。从内部条件来说，鸡卵孵化为小鸡的条件是                        ，从外部条件来说，鸡卵孵化所需的适宜条件有                  、湿度和通风等条件。

（3）下表是几种鸟卵孵化成雏鸟所需要的时间：

鸟名家燕麻雀家鸽鸡鸭天鹅鸵鸟
孵化时间╱天12---151417--1920---2228---3234---3845
由表中数据你得出的结论是                               。

答案

（1）筑巢（1分）  （2）4 胚盘（1分）  5 卵白（1分）   3 卵黄（1分）   6 气室（1分）  鸡卵必须是受精卵（2分） 适宜的温度（2分）

（3）一般来说，鸡卵体积越小，孵化期越短，鸟卵越大，孵化期越长（2分）

：（1）鸟的繁殖行为包括：求偶、交配、筑巢、产卵、孵卵、育雏几个阶段．诗句“谁家春燕啄春泥”描写了燕子繁殖行为中的筑巢行为．

（2）本题主要是考查鸟卵的结构及功能，其结构和功能依次为：

单项选择题

以下情形不属于用人单位单方面解除劳动合同的是______。

A．过错性解除B．非过错性解除C．经济性裁员 D．预告解除
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单项选择题

Government officials reported three new cases of mad cow, bringing the total so far this year to 99. Last year, France recorded just 31 cases of the mad cow disease. The rising numbers are in part (1) a new testing program that focuses on cows that are most (2) . That program has (3) 39 cases. But still 60 new cases were identified in the usual way, (4) were found in 1999. Many scientists (5) that this year, five years after safety precautions were (6) , the number of cases would be (7) .

The rise in cases has (8) some scientists to question whether the disease can be transmitted in ways not yet understood. Scientists are still (9) the disease, first recognized in cows in 1986.

It appears that it is not caused by a bacteria, virus or fungus, but (10) infectious particles called prion, perhaps (11) a virus or other agent. The disease kills cells in the brain, (12) it spongy and full of holes.

France has taken more steps to (13) safety than most European countries, (14) refusing to take English beef (15) the European Union. But some scientists believe that France has not been (16) in imposing the ban on feed that (17) animal pans.

Some French officials hope that the sudden interest in mad cow disease will mean that French consumers will become educated about it, thereby recognizing that French beef is actually (18) controlled. Every cow is given a passport at birth, and extensive information about its parentage and (19) it was raised must be (20) to any slaughterhouse. When a diseased animal is found, the entire herd is destroyed.

16（）

A.affective

B.efficient

C.effective

D.affect
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