日本和德国科学家分别在美国《科学》杂志和英国《自然》杂志上报道说,他们发现了 ___

题型:单项选择题

问题:

日本和德国科学家分别在美国《科学》杂志和英国《自然》杂志上报道说,他们发现了 ______这种生物化学酶在把氧气和食物转变成维持生命所必需的能量过程中发挥着关键作用。这种生化酶名为“细胞色素氧化酶”。

在他们各自的研究中,日本的科学家小组是借助聚焦于牛心脏组织的复杂三维立体 X光成像仪器获得其形状图像的,而德。国科学家小组则是从一种土壤细菌中制取的酶蛋白晶体中分离得到其结构的。“细胞色素氧化酶”存在于小到微生物、大到大象的所有动物的所有细胞中。在人体内,氧气进入肺叶后,被红血球吸收,然后输送到每一个细胞内,由“细胞色素氧化酶”与来自食物的氧分组合,通过化学反应产生二氧化碳、水和能量。最新研究显示了铁原子、铜原子以及其他元素在“细胞色素氧化酶”中的排列分布状况,①可帮助科学家发现细胞内某些新陈代谢过程发生差错的原因,②找到治疗过早衰老、神经系统功能衰退,③肥胖等相应疾病的方法和药物。科学家认为,以生命能量逐步丧失为特征的衰老的部分原因可能是由于“细胞色素氧化酶”作用效率下降的结果;而以能量积聚过多,脂肪细胞数量以及体重超出正常水平为特征的肥胖则可能是“细胞色素氧化酶”作用效率过高的结果。

第一自然段横线上,应填入的一项是()。

A.一种重要的生物化学的基本结构

B.一种重要的生物化学酶

C.一种名为“细胞色素氧化酶”的基本结构

D.一种名为“细胞色素氧化酶”

考点:国家公务员行政职业能力测试行政职业能力测试
题型:单项选择题

引起犬前列腺纤维型肥大的激素是()

A.雄性激素

B.雌性激素

C.前列腺素

D.垂体后叶素

E.肾素

题型:单项选择题

城市中的各项活动需要利用一定的土地,同类活动在空间上高度聚集,形成了功能区。据此回答问题。

小题1:下列关于城市功能区的叙述,正确的是

A.城市功能区的形成与城市的起源同步

B.功能区之间有明确的界线

C.各功能区的形成都是规划建设的结果

D.在不同城市,各类功能区的空间组合不尽相同小题2:功能区在城市中的区位及其变化是

A.商业区,都位于城市几何中心

B.工业区,逐渐向市区外缘移动

C.文化区,接近商业区布局

D.功能区一旦形成,不会发生变化

题型:单项选择题

只有氨基酸组成的蛋白质是().

A.单纯蛋白质

B.糖蛋白

C.核蛋白

D.脂蛋白

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Is test anxiety destructive. Can we make test anxiety work for us The answer to both of these questions is yes. Test anxiety often interferes with student performance but this same test anxiety, if channeled correctly, can help improve performance.
In order to lessen the destructive elements of test anxiety, the approach should be to develop improved confidence and knowledge. As your knowledge of the course material increases, your confidence in your ability to succeed will increase. As your confidence increases, your anxiety will go down, allowing your knowledge to come through more efficiently. The way you prepare for a test can reduce anxiety during the test.
You will be surprised how confident you will feel if you know the material. Studies of memory show if you want to be able to recall information from text or lecture you have to review that material several times. It is important to know your own abilities and operate accordingly. If you know that you learn best by listening, prepare a tape of significant material and listen to the tape.
Study partners or study groups are often useful for self-testing. Experience in stressful situations tends to lessen anxiety in those situations. One way to help yourself retrieve material is through the use of mnemonic codes. Learn a code that lets you remember complex material. Developing an outline for an essay question that you know will be on the test or memorizing a formula are forms of code development.
Students are often frustrated by the sheer volume of material that has to be studied in college. Many instructors conduct reviews, give hints, identify what is important to study, use handouts or overhead transparency outlines. These materials should be at the top of your study list. If the instructor took the time to identify them, you should assume that they will play an important part of the test. While knowledge acquired during test preparation can help reduce anxiety, it is another thing to take the test itself. Following are a few suggestions to help reduce anxiety during the test.
When I arrive at a test, I often find students flipping text pages at the last minute trying to cram it all in at the end. You would be better off trying to relax, meditating a little, and clearing your mind to allow yourself the ability to concentrate on the questions that are coming.
As soon as the instructor gives you the signal to start, dump out formulas, codes, outlines from your memory onto the test answer sheets so that you will not have to worry about whether you will remember the codes long enough until you get to the appropriate test question.
You can build your confidence if you go through the test and answer all of the questions that you know first. Go back and work on those questions that need greater analysis, or that need to be worked out or need to be guessed at and your anxiety will not kick in until later in the test.
For those of you whose anxiety increases as study and preparation increase, your goal should be to start concentrating on things that take your mind off the test, i. e. , television, books, hobbies, movies, etc. Meditation and aerobic exercise have proven to be very useful methods for reducing undesirable effects of stress.
The solution to reducing the destructive influences of stress is to plan to study. Map out a schedule of when you will study each day. Identify the specific topics that you will study each day. Identify the areas of the material that you have had problems with and study those. Your plan should include reading the text material, reviewing notes and homework assignments, identifying material that needs further explanation, developing codes for memory material and testing yourself. Once you have studied adequately, your confidence will be fairly high, your knowledge will be satisfactory to do well on the test and the stomach butterflies will help you focus on the task at hand.
I’d wish you good luck on finals, but you and I both know that the more effectively you study, the luckier you will get.

According to the passage, your study plan probably does NOT include ______.

A.identifying the areas of the material that you have had problems with

B.identifying the specific topics that you’ll study each day

C.mapping out a schedule of when you’ll study each day

D.mapping out a schedule of when you will meditate and do aerobic exercise

题型:单项选择题

债务履行期届满抵押权人未受清偿时,抵押物的所有权可以自动转移为债权人所有。()

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