如图是关节结构示意图，请据图回答下列问题：

    There are purple clothes, purple handbags, purple bicycles, purple furniture, even purple computers! So purple is one of the most1colors today. But in the past, purple was a very expensive and unusual color. Let's take a look at the rich2of the color purple.

    Some scientists believe that the first plants to appear on Earth over 500 million years ago3looked purple, not green. Plants today are green because4use green chlorophyll (叶绿素) to produce energy.5these early plants probably used something called retinal, which is a dark purple color.

    During the time of the roman Empire (37 BC-476 AD), it was very6to make purple dye (染料). The dye came from sea snails (海螺) .But10.000 dead sea snails7you just one gram (克)of purple dye… as well as a very bad smell! This8purple dye was called Tyrian purple, and it was the preferred9of emperors.

    In 16th--century England, purple was10for the king's family members. Queen Elizabeth Is clothes were purple, but ordinary people were not allowed to11the color.

    In 1856. William Perkin, an 18-year-old12student, noticed something strange while doing an experiment (实验). The chemicals (化学药品) he used to clean his instruments13with the chemicals he used in his experiment and produced a bright purple color. This14Perkin to start a company using this chemical mixture to make purple dye. The dye was much15than sea snail dye. Thanks to Perkin, now anyone can afford to wear purple clothes.

******指出，要加强对权力运行的制约和监督，把权力关进制度的笼子里。古今中外人类都做了有益的探索，它一直在拷问着人类的政治智慧。阅读下列材料，回答问题。  

材料一   西汉统治时期，御史大夫专门行使监督权，其下属御史申丞专门负责监督王室和宫廷，也可以说是监察皇帝的；另一下属御史丞则负责监督政府，不论中央、地方都在内。……唐代单独设立御史台，其职权限于监察政府。但在政府中，仍存在专责监督皇帝的，那就是谏官，谏官由宰相任命，宋朝谏官改由皇帝任命，他们就不再监督皇帝，反过来监督宰相。  

——《我国古代政治制度的宪法学透视》  

材料二   罗马的法律贤明地把国家的权力分配给许多高级官吏，这些官吏之间起支持、制止和限制的作用；……它永远能够制裁任何滥用权力的事件；罗马共和国还设立了监察制度……使保民官和野心家不能操纵选举，使甚至人民自己也不能滥用自己的权力。  

——摘编自孟德斯鸠《罗马盛衰原因论》  

材料三   美国的行政监督系统，包括议会监督、政府内部监督、司法监督和社会监督等。行政监察的任务被分散在各个部门分别执行，没有专门负责行政效能监察的机构。但是……公职人员受到议会、法院、民众和舆论各方面强有力的监督，因而官僚主义和低效率等情况较少，工作效率较高。  

——摘编自《西方行政监察制度对中国的启示》  

材料四   第2条  中华人民共和国的一切权力属于人民。人民行使权力的机关是全国人民代表大会和地方各级人民代表大会。全国人民代表大会、地方各级人民代表大会和其他国家机关，一律实行民主集中制。  

第17条  一切国家机关必须依靠人民群众，经常保持同群众的密切联系，倾听群众的意见，接受群众的监督。  

第18条  一切国家机关工作人员必须效忠人民民主制度，服从宪法和法律，努力为人民服务。  

——1954年《中华人民共和国宪法》（节选）  

被誉为“火山之国”的国家是（　　）