鸟的受精卵从母体产出后，就暂停发育，主要原因是。

发布时间：2017-05-24 12:36 │ 来源：www.tikuol.com

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鸟的受精卵从母体产出后，就暂停发育，主要原因是。

考点：鸟的生殖和发育

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张老师编写了一本《数学童话》，得到稿费3800元．按规定，一次稿费超过800元的部分，应该以14%的税率纳税．张老师应该缴纳税款______元，他实际得到稿费______元．

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回旋加速器是用来加速带电粒子的装置，如图所示. 它的核心部分是两个D形金属盒，两盒相距很近，分别和高频交流电源相连接，两盒间的窄缝中形成匀强电场，使带电粒子每次通过窄缝都得到加速。两盒放在匀强磁场中，磁场方向垂直于盒底面，带电粒子在磁场中做圆周运动，通过两盒间的窄缝时反复被加速，直到达到最大圆周半径时通过特殊装置被引出。如果用同一回旋加速器分别加速氚核（）和α粒子（）比较它们所加的高频交流电源的周期和获得的最大动能的大小，有

A.加速氚核的交流电源的周期较大，氚核获得的最大动能也较大

B.加速氚核的交流电源的周期较大，氚核获得的最大动能较小

C.加速氚核的交流电源的周期较小，氚核获得的最大动能也较小

D.加速氚核的交流电源的周期较小，氚核获得的最大动能较大

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关于高血压病的治疗，下列哪项是错误的（）

A.年轻人高血压，将血压控制在130/80mmHg以内

B.老年人单纯收缩期高血压，将血压控制在160mmHg左右

C.老年人高血压，可将血压降至140]90mmHg以下

D.对于血压控制不理想者，可采用两种以上降压药物联合应用

E.根据高血压病人的具体情况，调整降压药的种类与剂量

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放射性污染物不包括（）。

A、核工业废料

B、核武器

C、工业生产中的“三废”

D、医用放射源

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Cooperation is the common endeavor of two or more people to perform a task or reach a jointly cherished goal. Like competition and conflict, there are different forms of cooperation, based on group organization and attitudes.
In the first form, known as primary cooperation, group and individual unite. The group contains nearly all of each individual’s life. The rewards of the group’s work are shared with each member. There is an interlocking identity of individual, group, and task performed. Means and goals become one, for cooperation itself is valued.
While primary cooperation is most often characteristic of preliterate societies, secondary cooperation is characteristic of many modem societies. In secondary cooperation, individuals devote only part of their lives to the group. Cooperation itself is not a value. Most members of the group feel loyalty, but the welfare of the group is not the first consideration. Members perform tasks so that they can separately enjoy the fruits of their cooperation in the form of salary, prestige, or power. Business offices and professional athletic teams are examples of secondary cooperation.
In the third type, called tertiary cooperation or accommodation, latent conflict underlies the shared work. The attitudes of the cooperating parties are purely opportunistic; the organization is loose and fragile. Accommodation involves common means to achieve antagonistic goals; it breaks down when the common means cease to aid each party in reaching its goals. This is not, strictly speaking, cooperation at all, and hence the somewhat contradictory term antagonistic cooperation is sometimes used for this relationship.

The underlined word "cherished" in Paragraph 1 is closest in meaning to ______.

A．prized

B．based on

C．defined

D．set up

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