《微生物学》课程PPT课件讲稿（英文版）Lecture 1

Lecture 1 1.1 Microbiology 1.2 Microorganisms as cells 1.3 Microorganism and Their Natural Environments 1.4 The Impact of Microorganisms on Humans

Lecture 1 • 1.1 Microbiology • 1.2 Microorganisms as Cells • 1.3 Microorganism and Their Natural Environments • 1.4 The Impact of Microorganisms on Humans

What is Microbiology? The science of microorganisms(very small, unicellular organisms The discipline is just over a century old Has given rise to molecular biology and biotechnology

What is Microbiology? • The science of microorganisms (very small, unicellular organisms) • The discipline is just over a century old • Has given rise to molecular biology and biotechnology

What are microbes? Prokaryotic Eukar otic Eukar ya Macroorganisms None known Animals Plants Archaea Eukar ya Algae Microorganisms Bacter ia FungI Protozoa

What are Microbes?

Figure 1.2a Bacterial cells viewed with light microscope

Figure 1.2a Bacterial cells viewed with light microscope

参 Fiqure 1.2b Bacterial cell viewed with electron microscope

Figure 1.2b Bacterial cell viewed with electron microscope

Root nodule

Root Nodule

Bacteroids within root nodule

Bacteroids within Root Nodule

1. Metabolism Uptake of chemicals from the environment, their transformation within the cell. and elimination of wastes into the environment the cell is thus an open system Cell Environment 2. Reproduction(growth) Chemicals from the environment are turned into new cells under the direction of preexisting cells

3. Differentiation Formation of a new cell structure such as a spore usually as part of a cellular life cycle. Spore 4. Communication Cells communicate or interact primarily by means of chemicals that are released or taken up ↓↑

5. Movement 6. Evolution Living organisms are often capable of self-propulsion Cells evolve to display new biological properties Phylogenetic trees show the evolutionary relationships between cells New species ancestral species