Chapter 1 - Humans and the Microbial World Flashcards
What are three benefits of microorganisms?
- Nitrogen Fixation
- Oxygen Production
- Degradation of Materials
How are microorganisms used in food production?
Yeast used in bread (2100 B.C.)
Fermentation of grains to make beer (1500 B.C.)
Fermentation of Milk (yogurt, cheese, buttermilk)
What is Biodegradation
The use of microorganisms to break down dangerous chemicals
ex: PCBs, DDT, trichloroethylene
oil spills
What is Bioremediation?
Using microorganisms to hasten decay of pollutants
What is Biotechnology?
Use of microbiological and biochemical techniques to solve practical problems
What is Genetic Engineering?
Introduction of genes into another organism
ex: disease resistant plants, production of medications (insulin)
In what years were most pathogenic bacteria identified?
1875-1918
True or False. All surfaces of the human body are populated by microorganisms?
True
What are Beneficial microbes?
- normal microbiota or normal flora
- prevent diseases by competing with pathogens
- development of immune system response
- aid in digestion
What do Pathogens do?
They damage body tissues and cause disease symptoms
-Cause infections
What are the three domains that all living things can be categorized into?
Bacteria, Archaea, and Eucarya
Which domain(s) are Prokaryotic Cells?
Bacteria and Archaea
Which domain(s) are Eukaryotic Cells
Eucarya
Are viruses, viroids, are prions part of the domains? Why?
No, because they aren’t living and viroids and prions aren’t cells
Do Bacteria have nuclei?
No, they are prokaryotes and prokaryotes do not have membrane-bound nuclei
Where is the DNA in a bacterium?
In a Nucleoid
What is the cell wall of Bacteria made of?
peptidoglycan, which is unique to bacteria
How do bacteria cells multiply?
Binary fission
What facilitates the movement in bacteria?
flagella
Are Archaea Eukaryotic or Prokaryotic?
Prokaryotic
What is a difference between Archaea and bacteria?
Archaea lack peptidoglycan in the cell walls and the ribosomal RNA sequences are different
S-layers – sheets of flat proteins or glycoprotein subunits
What is the term used to describe Archaea that survive in high salt concentration and temperature?
Extremophiles
What is the main differentiation between Eucarya and the other two domains?
They contain a true membrane-bound nucleus and other organelles
What microbial members are there of the domain Eucarya?
fungi, algae, protozoa
What are protists?
algae and protozoa
What is the accepted nomenclature for the naming of organisms?
The Genus capitalized and the species name (not capitalized)
- Genus and species always italicized or underlined (separate words and separate underlines)
ex: Escherichia coli or E. coli
What are Viruses?
Nucleic acid packaged in protein coat
What did Robert Hooke observe?
He observed cells and reported that living cells are composed of little boxes, or cells
What is the Cell Theory?
All living things are composed of cells and come from preexisting cells
