Microbiology of Human Pathogens
Chapter 1- 53 objectives
Microorganism - ANS-are organisms too small to be seen with the naked eye.
Microbe - ANS-microscopic life form; microorganism; germ includes acellular members
of the microbial world.
spontaneous generation - ANS-•Belief that life arises spontaneously from non-living
material
•Took over 200 years and many experiments to refute
Francesco Redi - ANS-demonstrated worms on rotting meat came from eggs of flies
landing on meat (1668)
•Placed meat in two jars
•Covered one jar with gauze
•Gauze prevented flies from depositing eggs
•No eggs →no worms
List scientists that were important in disproving spontaneous generation - ANS-a.
Francesco Redi
b. Louis Pasteur
c. John Tyndall
Louis Pasteur - ANS-demonstrated air is filled with microorganisms
Filtered air through cotton plug
•Observed trapped microorganisms
•Many looked identical to those found in broths
•Plug in sterilized broth gave rise to microorganisms
John Tyndall - ANS-showed evidence that some microbes have very high heat
resistance and are difficult to destroy
Biogenesis - ANS-describes the production of living things from other living things
endospores - ANS-•Heat-resistant form of bacteria
, Identify the reason why Pasteur's swan-necked flask results were not immediately able
to be replicated. - ANS-•Sterilizing broths required different times
•Some sterilized in 5 minutes; others not sterilized after 5 hours!
•Realized broths made from hay contained heat-resistant microbes
•Labs that could not reproduce Pasteur's results used broths made from hay
Germ Theory of Disease - ANS-The principle that microorganisms cause diseases
scientific method order - ANS-•Make an observation and ask a question about it
•Develop a testable explanation called a hypothesis
•Design experiments to test the hypothesis
•Include a control to help rule out alternative explanations
•Do the experiment, collect and analyze data
•Draw a conclusion
•Communicate methods, results, and conclusions
Scientific Method - ANS-describes the process of science
hypothesis - ANS-Develop a testable explanation
control - ANS-•to help rule out alternative explanations
theory - ANS-is an explanation supported by a large amount of evidence.
normal microbiota (also known as normal flora). - ANS-Human body carries enormous
population of microorganisms
Identify roles that normal microbiota fulfill in terms of the human body. - ANS-•Prevent
disease by competing with disease-causing microbes
•Aid in digestion
•Promote development of immune system
•May decrease allergies, asthma
•May affect brain chemistry and body weight
microbiome - ANS-•Total genetic content of the microbial community
•The microbial community itself
Identify what percentage of microbes can be cultured. (is it a lot or a little?) - ANS-Less
than 1% of microbes can be cultured
Chapter 1- 53 objectives
Microorganism - ANS-are organisms too small to be seen with the naked eye.
Microbe - ANS-microscopic life form; microorganism; germ includes acellular members
of the microbial world.
spontaneous generation - ANS-•Belief that life arises spontaneously from non-living
material
•Took over 200 years and many experiments to refute
Francesco Redi - ANS-demonstrated worms on rotting meat came from eggs of flies
landing on meat (1668)
•Placed meat in two jars
•Covered one jar with gauze
•Gauze prevented flies from depositing eggs
•No eggs →no worms
List scientists that were important in disproving spontaneous generation - ANS-a.
Francesco Redi
b. Louis Pasteur
c. John Tyndall
Louis Pasteur - ANS-demonstrated air is filled with microorganisms
Filtered air through cotton plug
•Observed trapped microorganisms
•Many looked identical to those found in broths
•Plug in sterilized broth gave rise to microorganisms
John Tyndall - ANS-showed evidence that some microbes have very high heat
resistance and are difficult to destroy
Biogenesis - ANS-describes the production of living things from other living things
endospores - ANS-•Heat-resistant form of bacteria
, Identify the reason why Pasteur's swan-necked flask results were not immediately able
to be replicated. - ANS-•Sterilizing broths required different times
•Some sterilized in 5 minutes; others not sterilized after 5 hours!
•Realized broths made from hay contained heat-resistant microbes
•Labs that could not reproduce Pasteur's results used broths made from hay
Germ Theory of Disease - ANS-The principle that microorganisms cause diseases
scientific method order - ANS-•Make an observation and ask a question about it
•Develop a testable explanation called a hypothesis
•Design experiments to test the hypothesis
•Include a control to help rule out alternative explanations
•Do the experiment, collect and analyze data
•Draw a conclusion
•Communicate methods, results, and conclusions
Scientific Method - ANS-describes the process of science
hypothesis - ANS-Develop a testable explanation
control - ANS-•to help rule out alternative explanations
theory - ANS-is an explanation supported by a large amount of evidence.
normal microbiota (also known as normal flora). - ANS-Human body carries enormous
population of microorganisms
Identify roles that normal microbiota fulfill in terms of the human body. - ANS-•Prevent
disease by competing with disease-causing microbes
•Aid in digestion
•Promote development of immune system
•May decrease allergies, asthma
•May affect brain chemistry and body weight
microbiome - ANS-•Total genetic content of the microbial community
•The microbial community itself
Identify what percentage of microbes can be cultured. (is it a lot or a little?) - ANS-Less
than 1% of microbes can be cultured
