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问题 选择题

男性产生生殖细胞的器官是

A．睾丸

B．阴茎

C．输精管

D．阴囊

答案

答案：A

题目分析：男性的性器官包括：精囊腺（分泌黏液）；前列腺（分泌黏液）；输精管（输送精子）； * * （排出精液和尿液）；阴茎；附睾（贮存和输送精子）；阴囊（保护睾丸和附睾）；睾丸（产生精子，分泌雄性激素）．

单项选择题

Most plants can make their own food from sunlight, (1) some have discovered that stealing is an easier way to live. Thousands of plant species get by (2) photosynthesizing, and over 400 of these species seem to live by pilfering sugars from an underground (3) of fungi(真菌). But in (4) a handful of these plants has this modus operandi been traced to a relatively obscure fungus. To find out how (5) are (6) , mycologist Martin Bidartondo of the University of California at Berkeley and his team looked in their roots. What they found were (7) of a common type of fungus, so (8) that it is found in nearly 70 percent of all plants. The presence of this common fungus in these plants not only (9) at how they survive, says Bidartondo, but also suggests that many ordinary plants might prosper from a little looting, too.

Plants have (10) relations to get what they need to survive. Normal, (11) plants can make their own carbohydrates through photosynthesis, but they still need minerals. Most plants have (12) a symbiotic relationship with a (13) network of what are called my corrhizal fungi, which lies beneath the forest (14) . The fungi help green plants absorb minerals through their roots, and (15) , the plants normally (16) the fungi with sugars, or carbon with a number of plants sharing the same fungal web, it was perhaps (17) that a few cheaters—dubbed epiparasites—would evolve to beat the system. (18) , these plants reversed the flow of carbon, (19) it into their roots from the fungi (20) releasing it as "payment.\

13（）

A.large

B.vast

C.great

D.big
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选择题

适应21世纪需要的人才，应具备思想政治素质、科学文化素质和身体心理素质等。从哲学上讲，这一共识符合（　　）

A．两点论和重点论相统一的观点

B．联系的、发展的、全面的观点

C．矛盾普遍性与特殊性的统一

D．认识来源于实践的观点
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