水生向陆生进化的动物类群是____，真正的陆生动是从____开始的．

面对新疆多次的恐怖主义袭击，主题班会上小梦同学提出：“让团结最有利，成为反恐最强音！”这一倡议要求我们（  ）
①自觉履行维护民族团结的义务
②积极建设平等、团结、共同繁荣的新型民族关系
③坚决同一切分裂国家的行为做斗争
④各民族同学互相关心、团结友爱

阅读下面短文，然后从所给的四个选项中选出一个最佳答案。

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已知一种锶原子的相对原子质量为88，其质子数是38，则一个这种锶原子中含有的微粒总数为____。

乳酸茵是存在于人体内的益生菌，能助消化，利于肠道健康，因此常用于酸奶的制作．回答下列问题：

（1）与腐乳制作所用微生物相比，乳酸菌在结构上的主要特点是____ ．

（2）大量生产乳酸菌一般用____．（填“固体”或“液体”）培养基，培养基中除添加必需的营养成分外，还需要注意控制____ 等培养条件．

（3）酸奶制作时杀菌很重要，牛奶一般用____ 法，所用仪器如接种环常用____ 法，接种室用____ 法．

（4）含有抗生素的牛奶____ （填“适合”或“不适合”）作为酸奶的制作原料．

（5）乳酸菌也常用于泡菜的制作，腌制泡菜过程中亚硝酸盐含量的变化是____．