《环境微生物学》教学资源（英文版）

Figure 1. 19 (a)The microscope used by Robert Hooke (be)Two drawings by Robert Hook of rst microscopic descriptions of microorganisms. (b)A blue mold growing on the surface of leather; the round structures contain spores of the muld. c)A mold growing on the surface of an aging, deteriorating ruse leaf

Antony van Leeuwenhoek (1632-1723) and his microscope Louis Pasteur(1822-1895) working in his laboratory

• Antony van Leeuwenhoek (1632-1723) and his microscope. • Louis Pasteur (1822-1895) working in his laboratory

Air forced out ) (a) Nonsterile liquld of flask Liquid sterilized poured into flask drawn out in Dust and microorganisms Liquid cooled Liquid remains slowly sterile for nany years Short time Microorgani grow in liquid liquid

Robert Koch (1843 1910 EXamining specImen in his laboratory

• Robert Koch (1843- 1910) Examining a specimen in his laboratory

Chapter 1 Introduction: An Overview of Microbiology and Cell Biology Postulate 1 organism should be preser in all cases of the diseas blood and absent from healthy animEs Suspecter Red blood cell Postulate 2 Streak agar plate with sample from ethe should be grow dIseased or healthy animal Colonie Inoculate healthy imal with cells suspected pathogen Postulate 3 Cells from n pute culture should cause disease in a Diseased ove blood or e sample and arve by microscopy Postulate 4 The organism should be Laboratory ed and show culture Figure 1.22 Koch's postulates for prov o original lowing isolation of a pure culture of the st Suspected pathogen Pure culture pected pathogen, a laboratory culture of th organism organism should both initiate the disease ar

Two fundamentally different types of cells exist. Procaryotic cells have a much simpler morphology than eucaryotic cells and lack a true membrane-delimited nucleus. All bacteria are procaryotic. In contrast, eucaryotic have a membrane enclosed nucleus; they are more complex morphologically and are usually larger than prokaryotes. Algae, fungi, protozoa higher plants, and animals are eucaryotic Procaryotic and eucaryotic cells differ in many other ways as well

• Two fundamentally different types of cells exist. Procaryotic cells have a much simpler morphology than eucaryotic cells and lack a true membrane-delimited nucleus. All bacteria are procaryotic. In contrast, eucaryotic have a membrane￾enclosed nucleus; they are more complex morphologically and are usually larger than prokaryotes. Algae, fungi, protozoa, higher plants, and animals are eucaryotic. Procaryotic and eucaryotic cells differ in many other ways as well

Bacteria consist of only a single cell, but dont let their small size and seeming simplicity fool you. Theyre an amazingly complex and fascinating group of creatures Bacteria have been found that can live in temperatures above the boiling point and in cold that would freeze your blood They eat"everything from sugar and starch to sunlight, sulfur and iron there's even a species of bacteria-Deinococcus radiodurans--that can withstand blasts of radiation 1,000 times greater than would kill a human being ASt Cial

• Bacteria consist of only a single cell, but don't let their small size and seeming simplicity fool you. They're an amazingly complex and fascinating group of creatures. Bacteria have been found that can live in temperatures above the boiling point and in cold that would freeze your blood. They "eat" everything from sugar and starch to sunlight, sulfur and iron. There's even a species of bacteria—Deinococcus radiodurans—that can withstand blasts of radiation 1,000 times greater than would kill a human being

16 Chapter 1 Introduction: An Overview of Microbiology and Cell Biology (b) Figure 1. 14 Colonies formed on an agar-containing medium on a I'etri plate(a)Red colonies of the bacterium Serratia marcescens(top half of plate)streaked alongside colonies of a mutant derivative unable to make the red pigment(bottom half of plate).(b)Mixed colonies of ye low and purple pigmented bacteria

1.7 Laboratory Culture of microorganisms Figure 1. 13 Examples of microbial communities. (a)Adense com munity of algae and cyanobacteria in the surface waters of a nutri- ent-rich lake(Lake Mendota, Wisconsin).(b) Photomicrograph of a bacterial community that developed in the depths of a small lake (Wintergreen Lake, Michigan), showing cells of various sizes