1. Chapter 1: The Main Themes of Microbiology.

2. I. The Scope of Microbiology
A. Microbiology is the specialized study of microorganisms, microbes and viruses.
1. There are several groups of microorganisms including bacteria, algae, protozoa, helminths (parasitic worms) and fungi.
2. All microorganisms can be infected by viruses.

3. B. Microorganisms are easy to study because they reproduce quickly but also difficult to study because of their small size.
C. Microbiologists study every aspect of microbes including their structure and function.
D. The study of microbiology has led to a greater understanding of the chemistry of life/biochemistry.

4. II. The Impact of Microbes on Earth
A. Microbes have extensively shaped Earth’s habitats and the evolution of other life forms.

7. B. Single celled organisms arose on Earth about 3.5 billion years ago.
1. Three types of cells arose/evolved from the original type: bacteria and Achaea (prokaryotes) and eukaryotes.
C. Bacteria have been on Earth two billion years longer than the earliest animals and probably should not be eliminated.
D. Life in its present form would not be possible without the evolution of microbes.
E. Microbes are found nearly everywhere on Earth and play a central role to life on Earth.

8. F. Evolution is the accumulation of changes that occur in organisms as they adapt to their environments.
G. The Theory of Evolution has undergone years of testing and has not yet been disproven.

9. H. Microbes are deeply involved in the flow of energy and food through the Earth’s ecosystems.
1. Microbes/bacteria invented photosynthesis long before plants evolved.
2. Bacteria are responsible for changing the atmosphere of the Earth from one without oxygen to one with oxygen.
3. Bacteria and algae account for 70% of Earth’s photosynthesis.

10. I. Decomposition and nutrient recycling unlock chemical elements for reuse.
1. Many of the gases that regulate the Earth’s temperature are produced by microbes. (CO2 and CH4)
2. A large number of microbes live beneath the Earth’s crust.
3. Microbes live in complex relationships with plants and animals (symbiosis).

12. III. Human Use of Microorganisms
A. The diversity and versatility of microbes make them purposeful in solving human problems.
1. Humans have been using microorganisms by accident or choice to improve life.
2. Bread, wine and beer production is aided by microorganisms
3. Biotechnology is the manipulation of microorganisms to make products in an industrial setting.

13. B. Genetic Engineering creates new products and genetically modified organisms (GMOs)
1. Recombinant DNA Technology makes it possible to transfer DNA from one organism into another.
2. R.D.T. has unlimited potential in the medical and agricultural industries.

14. C. GMOs can be used to produce insulin and hemoglobin efficiently at low cost.

16. D. Bioremediation involves the use of microbes to clean up toxic pollutants.
E. Microbes can also be used in the treatment of water and sewage.

17. IV. Infectious Disease and the Human Condition.
A. The vast majority of pathogens cause humans no direct harm and some actually benefit.
1. There are however 2,000 different microbes that can cause disease.
2. Infectious diseases are among the Top 10 causes of death per year in the United States.

18. B. Low income countries suffer higher rates of infectious death that high income countries.
C. Malaria caused by microbes that live in mosquitoes causes between 700,000 and 1.2 billion deaths worldwide each year.

20. D. Some old diseases like tuberculosis (TB) are reemerging.
E. There is emerging evidence that some cancers may be caused by bacteria and viruses.
F. 26% of cancers are attributed to microbes in low income countries compared to 7% in high income countries.
G. Longer life expectancy is causing the unexpected side effect of increasing infections within older populations of people.

22. V. The General Characteristics of Microorganisms.
A. The three basic cell lines differ in complexity and function.
1. Archaeal/bacteria cells are 10x smaller than eukaryotic cells.
2. All bacteria are microscopic and contain few organelles compared to eukaryotes.

24. B. Some microorganisms are free-living and some are parasitic.

25. VI. The Historical Foundations of Microbiology.
A. The science of microbiology is the combined work of many men and women over the last 300 years.
B. Before the invention of the microscope, the spread of disease was largely a mystery.

26. C. Robert Hooke is given the credit for discovering cells in the 1660’s with his primitive microscope.
D. Anton van Leeuwenhoek is given credit for discovering microbes in pond water at the end of the 1690’s with his more advanced microscope.
E. Leeuwenhoek also examined plaque from teeth and saw that microbes seemed to be everywhere.
F. Leeuwenhoek’s microscopes could magnify objects 300x.

27. Robert Hooke: Micrographia

28. Anton van Leeuwenhoek

29. E. Leeuwenhoek also examined plaque from teeth and saw that microbes seemed to be everywhere.
F. Leeuwenhoek’s microscopes could magnify objects 300x.
G. The microscopes that schools use today are very much the same as those available in the 1850’s (1000x).

30. H. The 2000’s are being called the Century of Biology due to all the new discoveries.
I. The discovery of restriction enzymes in the 1970’s has allowed scientists to cut DNA into smaller fragments to make it easier to study and manipulate.

31. J. The discovery of the PCR (Polymerase Chain Reaction) technique has allowed scientists to copy certain sequences/pieces of DNA for easier study. K. Genome sequencing has shown the importance of RNA in cell regulation.

32. L. In the late 1800’s, Robert Koch was the first to provide evidence of the link between certain microbes and certain diseases.
M. Joseph Lister was the first to introduce aseptic techniques aimed at reducing infections in the operating room.
N. Louis Pasteur introduced pasteurization as a way of eliminating microbes from food.

33. VII. Naming, Classifying and Identifying Microorganisms.
A. The science of classifying living organisms is called taxonomy. B. The taxonomic categories from top to bottom are: Kingdom, Phylum, Class, Order, Family, Genus and Species. C. In recent times the category of Domain has been added above Kingdom (Bacteria, Archaea and Eukarya).

34. Modern Taxonomy

35. D. Living organisms have both a common name and a scientific name.
E. The scientific name has two parts (binomial nomenclature) that includes the genus and species name.