MBIO 3401 FINAL EXAM SAMPLE QUESTIONS
AND ANSWERS | WITH COMPLETE SOLUTION
In the history of classification of microbes, who were the key historical contributors and
what were their key contributions?
Leeuwenhoek- an early microscopist, father of micro.
Robert hooke - built the first compound microscope
Robert koch - german physician & founder of the scientific method of microbiology ( the chain
of infection, or transmission of a disease
Leeuwenhoek
an early microscopist, father of micro.
Robert hooke
built the first compound microscope
Robert koch
german physician & founder of the scientific method of microbiology ( the chain of infection, or
transmission of a disease
Francesco redi
showed that maggots in decaying meat were the offspring of flies
Lazzaro spallanzani
showed that a sealed flask of meath broth sterilized by boiling failed to grow microbes
Louis pasteur
,began as an organic chemist
Globally where are microbes able to grow and not grow?
Microbes are able to grow virtually anywhere there are nutrients.
What are the typical size ranges of each major type of microbe?
Bacteria are typically 0.2-2µm
Eukaryotic microbes are 2µm-20cm
Prokaryotes 0.4
What microscopes most easily visualize moving flagella?
Using dark-field microscopy by Macnab and Ornston
What number of starting cells would produce any given number of final cells in log phase
growth after a specific number of generations?
log Nt = logN0 + nlog2
How is glucose transported into cells occur when energy sources (ATP/PEP etc) are not
available?
Glucose uniporter or non dependent glucose symporter
When and how can oxygen be toxic to cells, and how do cells mediate this toxicity?
There are certain reactions that can destroy the ROS (reactive oxygen species).
Catalase, peroxidase, FAD
What is the starvation response of cells?
, "Programmed cell death" which is dying cells release nutrients that neighboring cells can use to
survive.
One of the mechanisms used: toxin-antitoxin systems (TA).
How are petri plates sterilized before we use them?
autoclaving
Why don't bacteria grow in concentrated sugar solutions?
High sugar concentrations cause the bacterium to lose water by osmosis and it doesn't have any
cellular machinery to pump it back in against the osmotic gradient. Without enough water, the
bacteria can't grow or divide.
What is the appearance and molecular structure of the sac around bacterial cells
Peptidoglycan sacculus
Based on an image, how do some drugs function as weak acids or bases to enter cells?
Weak acids and bases will be able to penetrate the lipid cell membrane as they exist in their
unionized form
What coupled processes allow bacteria to function and divide so rapidly compared to
eukaryotes
Transcription and translation are coupled in bacteria but not eukaryotes, this allows for the
replication of dna/ translation of proteins to be done much quicker thus creating new bacterial
cells faster.
.What is polar aging?
AND ANSWERS | WITH COMPLETE SOLUTION
In the history of classification of microbes, who were the key historical contributors and
what were their key contributions?
Leeuwenhoek- an early microscopist, father of micro.
Robert hooke - built the first compound microscope
Robert koch - german physician & founder of the scientific method of microbiology ( the chain
of infection, or transmission of a disease
Leeuwenhoek
an early microscopist, father of micro.
Robert hooke
built the first compound microscope
Robert koch
german physician & founder of the scientific method of microbiology ( the chain of infection, or
transmission of a disease
Francesco redi
showed that maggots in decaying meat were the offspring of flies
Lazzaro spallanzani
showed that a sealed flask of meath broth sterilized by boiling failed to grow microbes
Louis pasteur
,began as an organic chemist
Globally where are microbes able to grow and not grow?
Microbes are able to grow virtually anywhere there are nutrients.
What are the typical size ranges of each major type of microbe?
Bacteria are typically 0.2-2µm
Eukaryotic microbes are 2µm-20cm
Prokaryotes 0.4
What microscopes most easily visualize moving flagella?
Using dark-field microscopy by Macnab and Ornston
What number of starting cells would produce any given number of final cells in log phase
growth after a specific number of generations?
log Nt = logN0 + nlog2
How is glucose transported into cells occur when energy sources (ATP/PEP etc) are not
available?
Glucose uniporter or non dependent glucose symporter
When and how can oxygen be toxic to cells, and how do cells mediate this toxicity?
There are certain reactions that can destroy the ROS (reactive oxygen species).
Catalase, peroxidase, FAD
What is the starvation response of cells?
, "Programmed cell death" which is dying cells release nutrients that neighboring cells can use to
survive.
One of the mechanisms used: toxin-antitoxin systems (TA).
How are petri plates sterilized before we use them?
autoclaving
Why don't bacteria grow in concentrated sugar solutions?
High sugar concentrations cause the bacterium to lose water by osmosis and it doesn't have any
cellular machinery to pump it back in against the osmotic gradient. Without enough water, the
bacteria can't grow or divide.
What is the appearance and molecular structure of the sac around bacterial cells
Peptidoglycan sacculus
Based on an image, how do some drugs function as weak acids or bases to enter cells?
Weak acids and bases will be able to penetrate the lipid cell membrane as they exist in their
unionized form
What coupled processes allow bacteria to function and divide so rapidly compared to
eukaryotes
Transcription and translation are coupled in bacteria but not eukaryotes, this allows for the
replication of dna/ translation of proteins to be done much quicker thus creating new bacterial
cells faster.
.What is polar aging?
