题干

根据各类微生物的形态结构特点和新陈代谢类型,利用选择培养基和鉴别培养基,结合显微镜镜检以及菌落特征,可以把混杂在一起的大肠杆菌、硝化细菌、乳酸菌、酵母菌、金黄色葡萄球菌、圆褐固氮菌、尿细菌、纤维杆菌分离开来.下面是分离筛选的方法步骤,请根据各个步骤的条件,填写空格中的内容:首先配制一系列不同性质的固体培养基,然后进行高温灭菌.再将上述微生物的混合液分别接种到各种培养基上培养.
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    Many of us still tend to think that emotions can affect reasonable thought,and sometimes land us in trouble. But in recent years psychologists have taken quite a different view. Keith Oatley,Professor of Psychology at Glasgow University,is involved in the research which shows the fundamental importance of emotions.

    He believes we are very ambivalent about them:we think of our emotions as being unreasonable,but we also consider them as essential to being human. For example,Mr. Spock,a character in the television series Star Trek,is super­intelligent and he has no emotions at all. However,he is never made captain of the spaceship. Maybe,this is because Mr Spock is not the kind of person you can share your feelings with—a person who shows his emotions.

    As Professor Oatley points out,our emotions have very important functions,for example,fear. If we cross the road and a car approaches,we usually stop moving or step back. We stop what we are doing,check what we have done and pay very careful attention to the environment. The emotion of fear makes us take this small series of actions which,on average, help protect our safety.

    On the other hand,if things are going well and small problems come up,we find we can solve them with the resources we have to hand. As a consequence, we tend to feel happy and usually continue doing the job.

    Anger is an emotion that tends to occur when someone is preventing us from doing something. Then this small “kit” of reactions enables us to prepare ourselves to be quite aggressive to that person,or to try harder,and so on.

    Professor Oatley believes emotions generally occur at these important moments in actions. With fear and anger our emotions make us decide to start doing something else, while with happiness they “suggest” we continue what we are already doing.