Lecture 1: Course Introduction and Brief History of Microbiology

Question 1

What does “germ” refer to?

Answer 1

A rapidly growing cell.

Question 2

What type of acellular biological entities are studied by microbiologists?

Answer 2

• Viruses
  
  • composed of protein and nucleic acid
• Viroids
  
  • composed of RNA
• Satellites
  
  • composed of nucleic acid, often RNA
• Prions
  
  • composed of protein

Question 3

What type of cellular organisms do microbiologists study?

Answer 3

• Fungi
  
  • e.g., yeasts and molds
• Protists
  
  • e.g., algae, protozoa, slime molds
• Bacteria
  
  • e.g., E. coli
• Archaea
  
  • e.g., methanogens

Question 4

What is fermentation?

Answer 4

The conversion of sugar to alcohol to make beer and wine.

Question 5

How do bacteria spoil wine?

Answer 5

Bacteria that use alcohol and produce acetic acid spoil wine by turning it to vinegar (acetic acid).

Question 6

What are Koch’s Postulates?

Answer 6

1. The same pathogen must be present in every case of the disease.
2. The pathogen must be isolated from the diseased host and grown in pure culture.
3. The pathogne from the pure culture must cause the disease when it is inoculated into a healthy, susceptible laboratory animal.
4. The pathogen must be isolated from the inoculated animal and must be shown to be the original organism.

**Robert Koch proved that a bacterium causes anthrax and provided the experimental steps, Koch’s Postulates, to proe that a specific microbe causes a specific disease.

Question 7

What are Koch’s postulates used for?

Answer 7

Koch’s postulates are used to prove the cause of an infectious disease.

• some pathogens can cause several disease conditions
• some pathogens cause disease only in humans
• using humans in completing the postulates is unethical
• molecular and genetic evidence may replace and overcome these limits

Question 8

What techniques were developed (discovered) from Koch’s work?

Answer 8

• agar
• Petri dishes
• nutrient broth and nutrient agar
• methods for isolating microorganisms

Question 9

What is chemotherapy?

Answer 9

Treatment with chemicals.

Question 10

Chemotherapeutic agents used to treat infectious disease can be?

Answer 10

synthetic drugs or antibiotics

Question 11

What are antibiotics?

Answer 11

Chemicals produced by bacteria and fungi that inhibit or kill other microbes.

Question 12

What tools are used in the study of microbiology?

Answer 12

• microscopes
• culture techniques
• molecular genetics
• genomics

Question 13

What are some modern developments in microbiology?

Answer 13

• bacteriology
• mycology
• virology
• parasitology
• immunology

Question 14

What is some recombinant DNA technology?

Answer 14

• microbial genetics
  
  • study of how microbes inherit traits
• molecular biology
  
  • study of how DNA directs protein synthesis
• genomics
  
  • study of an organism’s genes
• recombinant DNA
  
  • DNA made from two different sources

Question 15

What three groups are microorganisms divided into based on their compared ribosomal RNA genes?

Answer 15

• Bacteria (true bacteria)
• Archaea
• Eukarya (eukaryotes)

Question 16

Name 7 types of microorganisms.

Answer 16

1. bacteia
2. archaea
3. fungi
4. protozoa
5. algae
6. viruses
7. multicellular animal parasites

Question 17

Each organism has two names, what are they?

Answer 17

• Genus
  
  • capitalized
• Specific Epithet
  
  • lowercase