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曾令许多人恐慌并影响大半个中国及三十几个国家的非典型肺炎(即SARS),其元凶不是细菌,而是一种冠状病毒。在生物界,细菌和病毒是广泛存在的微生物。那么什么是细菌?什么是病毒?细菌是一种单细胞微生物,它的体积微小,我们的肉眼不能直接见到。一般用光学显微镜才能看到它的个体。由于菌体形态呈杆状、球状和弧状,所以就分别称杆菌,球菌和弧菌。细菌的大小通常用微米(10~3mm)计算。细菌的大小从0.5到2微米,它由细胞壁,细胞膜,细胞质和细胞核所组成。就像我们熟悉的生鸡蛋一样。细菌的繁殖速度很快,每20分钟就可由1个分裂
Many people have panicked and affected atypical pneumonia (SARS) in most of China and over 30 countries. The culprit is not a bacterium, but a coronavirus. In the biological world, bacteria and viruses are widespread microorganisms. So what is bacteria? What is a virus? Bacteria is a single-celled microorganisms, its small size, our naked eye can not be seen directly. It can only be seen with an optical microscope. As the cell morphology was rod-shaped, spherical and arc-shaped, so were called bacilli, cocci and Vibrio. The size of bacteria is usually calculated in microns (10 ~ 3mm). Bacteria range in size from 0.5 to 2 microns and consist of the cell wall, cell membrane, cytoplasm, and nucleus. Like we are familiar with raw eggs. Bacteria multiply fast, every 20 minutes by a split