题干

下列均属于原核生物的是(    )

A:青霉菌、小球藻

B:酵母菌、破伤风杆菌

C:蓝藻、硝化细菌

D:醋酸杆菌、蘑菇

上一题 下一题 0.0难度 选择题 更新时间:2020-02-06 02:31:12

答案(点此获取答案解析)

C

同类题1

根据短文理解,选择正确答案。

    Once when I was facing a decision that involved high risk, I went to a friend. He looked at me for a moment, and then wrote a sentence containing the best advice I've ever had: Be bold and brave — and mighty forces will come to your aid.

    Those words made me see clearly that when I had fallen short in the past, it was seldom because I had tried and failed. It was usually because I had let fear of failure stop me from trying at all. On the other hand, whenever I had plunged into deep water, forced by courage or circumstance, I had always been able to swim until I got my feet on the ground again.

    Boldness means a decision to bite off more than you can eat. And there is nothing mysterious about the mighty forces. They are potential powers we possess: energy, skill, sound judgment, creative ideas — even physical strength greater than most of us realize.

    Admittedly, those mighty forces are spiritual ones. But they are more important than physical ones. A college classmate of mine, Tim, was an excellent football player, even though he weighed much less than the average player. “In one game I suddenly found myself confronting a huge player, who had nothing but me between him and our goal line,” said Tim. “I was so frightened that I closed my eyes and desperately threw myself at that guy like a bullet — and stopped him cold.”

    Boldness — a willingness to extend yourself to the extreme—is not one that can be acquired overnight. But it can be taught to children and developed in adults. Confidence builds up. Surely, there will be setbacks (挫折) and disappointments in life; boldness in itself is no guarantee of success. But the person who tries to do something and fails is a lot better off than the person who tries to do nothing and succeeds.

    So, always try to live a little bit beyond your abilities—and you'll find your abilities are greater than you ever dreamed.

同类题5

阅读材料,回答下列问题。

材料一  在罗马早期,军队的服役期非常短。随着战争规模的升级,服役期变得越来越长,而符合征兵财产要求的公民越来越少。执政官马略规定,士兵一旦入伍,必须服役满16年。服役期间,由国家统一供养,并按照等级发给薪酬。……马略接受了罗马军团逐步向方阵队形演变的趋向,把步兵大队作为基本的战术组织。他强化了长矛兵的地位,将长矛方阵置入军队主力之中。他将重步兵按照训练程度重新划分了军团,还极大强化了远程火力和骑兵。事实证明,马略的军事改革对维护奴隶制国家确有实际效果,在不到一百年的时间里,权力在统帅们之间辗转,罗马共和国在一系列的内战后迅速转变为罗马帝国。——爱德华•吉本《罗马帝国衰亡史》

材料二  1901年,清朝下令停止武举,命各省筹建武备学堂,并决定裁汰20%至30%的绿营和防勇,建立按西方国家的营制、采用洋操训练、使用洋枪、洋炮的“常备军”。……直到清朝覆亡,总共只编成十四镇和十八个混成协(旅)、又四标(团)及禁卫军一镇,约17万人左右。……为争夺“新军”的指挥权,激化了满、汉统治集团之间的矛盾。由于“新军”军官多选用国内外军事学校毕业生,对士兵也要求具有某些文化知识,从而为革命知识分子的活动提供了条件,最终使“新军”成为一支反清力量,这是清朝统治者始料不及的。——摘编自李侃等《中国近代史》