MIBO 3500 EXAM 1 (JENNIFER WALKER)
What is a microbe? - Answers -an organism that requires a microscope to be seen.
Each microbe contains in its genome the capacity to reproduce its own kind.
The three domains of life? - Answers -Analysis of DNA sequences reveals the ancient
divergence of three domains of living organisms: Bacteria and Archea (Prokaryotes)
and eukarya (eukaryotes).
What data was used by Carl Woese to differ organisms into the domains? - Answers -
Woese used 16s rRNA comparisons in organisms to classify into 3 domains.
What are some microbial contradictions? - Answers -1. Supersize microbial cells
(Thiomargarita namibiensis)
2. Microbial communities (biofilms -- plaque on teeth)
3.Virus sizes
What is a genome? - Answers -The total genetic information contained in an organism's
CHROMOSOMAL DNA.
What is a metagenome? - Answers -The collection of sequences taken directly from the
ENVIRONMENT.
-- Acquire environmental sample
-- Lise the cells
-- cypher through DNA
What does metagenome analysis allow? - Answers -Allows for the discovery of new
microbes without having to isolate and grow them in vitro.
What ways do you think microbes have affected human history? - Answers -TB from
World War I and II. Aids --> sexual contraception, and Influenza and Amoxicillin.
Why did two-thirds of Saiga antelope drop dead? - Answers -A bacteria called
Pastuerella multocida type B. They normally live harmlessly in the long nose of the
antelope, but it suddenly invaded the rest of the body.
Germ theory of disease (Robert Koch) - Answers -Established a causative link between
an infectious agent and a disease. -- Koch's postulates
-- To prove a particular bacterium caused a specific disease, a PURE culture of
microorganisms was needed.
Koch's first Postulate - Answers -The microbe is found in all cases of the disease but is
absent from healthy individuals. (Used rabbits as lab rats)
, Koch's second Postulate - Answers -The microbe is isolated from the diseased host
and grown in pure culture.
Koch's third Postulate - Answers -When the microbe is introduced into a healthy,
susceptible host, the same disease occurs.
Koch's fourth Postulate - Answers -The same strain of microbe is obtained from the
newly diseased host.
What type of microbe induced diseases may NOT be identified through Koch's
Postulates? - Answers -A prion infection "Mad Cow" disease can not use Koch's
Postulates.
Who used Koch's Postulates to identify gastric ulcers were caused by Helicobacter
pylori? - Answers -Drs. Barry Marshall and Robyn Warren followed Koch's postulates to
prove Helicobacter pylori was the pathogen that induced gastric ulcers (1985)
--Awarded Nobel Price in 2005
What does analysis of 16s rRNA sequence show? - Answers -It shows that Archaea
are as distant from bacteria as from eukaryotes
What is Resolution? - Answers -It is the smallest distance by which two objects can be
separated and still be distinguished.
--the resolution of the human retina is about 150 (1/7mm)
What determines the function of a microbe? - Answers -Structure of the microbe
What are the common shapes of bacteria? - Answers -Bacillus (long rod shape),
spirochete (corkscrew), Cocci (circular, usually in pairs, grow together)
What is Bright-field Microscopy? - Answers -Generates a dark image of an object over
a light background.
-To increase resolution
--Use shorter wavelength
--Lessen contrast
--Use immersion oil (The use of oil at 100x helps minimize refraction and increase
resolution)
What is fixation? - Answers -Cells are made to adhere to a slide in a fixed position
What is staining? - Answers -Most stains have conjugated double bonds or aromatic
rings, and one or more positive charges to adhere to cells.
What does a simple stain do? - Answers -It adds dark color specifically to cells, but not
to the external medium or surrounding tissue.
What is a microbe? - Answers -an organism that requires a microscope to be seen.
Each microbe contains in its genome the capacity to reproduce its own kind.
The three domains of life? - Answers -Analysis of DNA sequences reveals the ancient
divergence of three domains of living organisms: Bacteria and Archea (Prokaryotes)
and eukarya (eukaryotes).
What data was used by Carl Woese to differ organisms into the domains? - Answers -
Woese used 16s rRNA comparisons in organisms to classify into 3 domains.
What are some microbial contradictions? - Answers -1. Supersize microbial cells
(Thiomargarita namibiensis)
2. Microbial communities (biofilms -- plaque on teeth)
3.Virus sizes
What is a genome? - Answers -The total genetic information contained in an organism's
CHROMOSOMAL DNA.
What is a metagenome? - Answers -The collection of sequences taken directly from the
ENVIRONMENT.
-- Acquire environmental sample
-- Lise the cells
-- cypher through DNA
What does metagenome analysis allow? - Answers -Allows for the discovery of new
microbes without having to isolate and grow them in vitro.
What ways do you think microbes have affected human history? - Answers -TB from
World War I and II. Aids --> sexual contraception, and Influenza and Amoxicillin.
Why did two-thirds of Saiga antelope drop dead? - Answers -A bacteria called
Pastuerella multocida type B. They normally live harmlessly in the long nose of the
antelope, but it suddenly invaded the rest of the body.
Germ theory of disease (Robert Koch) - Answers -Established a causative link between
an infectious agent and a disease. -- Koch's postulates
-- To prove a particular bacterium caused a specific disease, a PURE culture of
microorganisms was needed.
Koch's first Postulate - Answers -The microbe is found in all cases of the disease but is
absent from healthy individuals. (Used rabbits as lab rats)
, Koch's second Postulate - Answers -The microbe is isolated from the diseased host
and grown in pure culture.
Koch's third Postulate - Answers -When the microbe is introduced into a healthy,
susceptible host, the same disease occurs.
Koch's fourth Postulate - Answers -The same strain of microbe is obtained from the
newly diseased host.
What type of microbe induced diseases may NOT be identified through Koch's
Postulates? - Answers -A prion infection "Mad Cow" disease can not use Koch's
Postulates.
Who used Koch's Postulates to identify gastric ulcers were caused by Helicobacter
pylori? - Answers -Drs. Barry Marshall and Robyn Warren followed Koch's postulates to
prove Helicobacter pylori was the pathogen that induced gastric ulcers (1985)
--Awarded Nobel Price in 2005
What does analysis of 16s rRNA sequence show? - Answers -It shows that Archaea
are as distant from bacteria as from eukaryotes
What is Resolution? - Answers -It is the smallest distance by which two objects can be
separated and still be distinguished.
--the resolution of the human retina is about 150 (1/7mm)
What determines the function of a microbe? - Answers -Structure of the microbe
What are the common shapes of bacteria? - Answers -Bacillus (long rod shape),
spirochete (corkscrew), Cocci (circular, usually in pairs, grow together)
What is Bright-field Microscopy? - Answers -Generates a dark image of an object over
a light background.
-To increase resolution
--Use shorter wavelength
--Lessen contrast
--Use immersion oil (The use of oil at 100x helps minimize refraction and increase
resolution)
What is fixation? - Answers -Cells are made to adhere to a slide in a fixed position
What is staining? - Answers -Most stains have conjugated double bonds or aromatic
rings, and one or more positive charges to adhere to cells.
What does a simple stain do? - Answers -It adds dark color specifically to cells, but not
to the external medium or surrounding tissue.
