王伟同学正在做“呼吸时气体成分的变化”的探究实验,他设计的实验如图,甲乙两个瓶中

题型:探究题

问题:

王伟同学正在做“呼吸时气体成分的变化”的探究实验,他设计的实验如图,甲乙两个瓶中都装有澄清的石灰水。在吸入气体时,左手捏紧橡皮管,右手松开。在呼出气体时,右手捏紧橡皮管,左手松开。结果,乙瓶中的石灰水明显变浑浊。

(1)甲瓶在这个实验中起_________作用。

(2)从浑浊程度来看,乙瓶较甲瓶浑浊,说明呼出的气体中______的含量较多。气体发生这种变化的原因是___________。

考点:肺泡与血液的气体交换科学研究方法
题型:探究题

In much of Asia, especially the so-called “rice bowl” cultures of China, Japan, Korea,   41   Vietnam, food is usually eaten with chopsticks.

Chopsticks are usually two long, thin pieces of wood or bamboo. They can also be made of plastic, animal bone or metal. Sometimes chopsticks are quite artistic. Truly elegant chopsticks might  42   (make)of gold and silver with Chinese characters. Skilled workers also combine various hardwoods and metal  43  (create)special designs.

The Chinese have used chopsticks for five thousand years. People probably cooked their food in large pots, 44  (use) twigs(树枝) to remove it. Over time,  45  the population grew, people began cutting food into small pieces so it would cook more quickly. Food in small pieces could be eaten easily with twigs which  46  (gradual)turned into chopsticks.

Some people think that the great Chinese scholar Confucius,  47  lived from roughly 551 to 479 B.C., influenced the  48  (develop) of chopsticks. Confucius believed knives would remind people of killings and  49   (be) too violent for use at the table.

Chopsticks are not used everywhere in Asia. In India, for example, most people traditionally eat   50  their hands.

41()

题型:探究题

下列毒素中,属于神经毒素的是()。

A.白喉毒素

B.红疹毒素

C.肉毒毒素

D.产气荚膜梭菌α毒素

E.葡萄球菌毒性休克综合征毒素

题型:探究题

审计报告的编写要求包括:

A.要陈述要客观

B.详细说明审计风险

C.内容要完整

D.编制程序要规范

E.要详细说明审计过程

题型:探究题

下列工具中,解放了人力的是()。

①水排

②筒车

③翻车

④曲辕犁

A.①②③④

B.①②

C.①②③

D.②③④

题型:探究题

抵债资产处置后会造成信贷资产损失的资产必须经过评估机构评估定价。

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