Exam 1 Flashcards
Which is the correct usage of binomial nomenclature?
- Escherichia coli
- Escherichia coli
- escherichia coli
- Escherichia Coli
- E.coli
E.coli
Who first observed prokaryotic microbes?
- Carolus Linnaeus
- Anton van Leeuwenhoek
- Robert Hooke
- Louis Pasteur
- Robert Koch
- Anton van Leeuwenhoek
Which statement is not true?
- Microbes are used in producing fermentation products such as vinegar and alcoholic beverages.
- Microbes help recycling chemical elements between the soil, water, life, and air.
- Only microorganisms can fix nitrogen gas from the air.
- Many more microorganisms in nature are harmful than are beneficial.
- Some microbes in intestines are important for digestion and the synthesis of some vitamins.
- Many more microorganisms in nature are harmful than are beneficial.
_____ observed the fruiting bodies, the reproductive structures of molds, and describe them in his book “Micrographia.”
- Louis Pasteur
- Anton van Leeuwenhoek
- Robert Hooke
- Carolus Linnaeus
- Robert Koch
- Robert Hooke
Koch’s success in proving the germ theory of disease was mainly due to the development of ___.
- boiling jar
- sterile meat broth
- microscope
- aseptic technique
- pure culture
- pure culture
Streptomycin is an example of _____ because it is produced by the soil microbe Streptomyces griseus.
- antimicrobial dyes
- synthetic drugs
- antibiotics
- magic bullets
- salvarsans
- antibiotics
The process by which microbes turn grape juice into wine is called ________.
- respiration
- pasteurization
- sterilization
- fermentation
- vaccination
- fermentation
Which of the following is NOT a domain in Woese phylogenetic tree?
- Bacteria
- Plantae
- Archaea
- Eukarya
- All of the above are domains in Woese phylogenetic tree.
- Plantae
“Bacillus” in microbiology has more than one meaning. Which is NOT one of them?
- a bacterial shape.
- rod-shape.
- a specific genus.
- pleomorphic.
- “Bacillus” may mean all of the above.
- pleomorphic.
Spherical bacterial cells in grape-like clusters would be referred to as a ______ arrangement.
- streptobacillus
- vibrio
- staphylococcus
- streptococcus
- spiral
- staphylococcus
consider the substances that surround bacterial cells that are viscous polymer of polysaccharide, polypeptide, or both.
What is the general term for these substances?
- peptidoglycan
- cell wall
- glycocalyx
- biofilm
- outer shell
- glycocalyx
consider the substances that surround bacterial cells that are viscous polymer of polysaccharide, polypeptide, or both.
Streptococcus mutans has ___ that is unorganized and loosely attached to the cell wall.
- biofilm
- fimbriae
- capsule
- outer membrane
- slime layer
- slime layer
consider the substances that surround bacterial cells that are viscous polymer of polysaccharide, polypeptide, or both.
Which is NOT a function of these substances in bacteria?
- to protect pathogenic bacteria from phagocytosis by the host cells.
- to serve as an extracellular polymeric substance (EPS) in biofilm.
- to provide motility to the bacterial cells .
- to enable the bacterial cells to survive by attaching to various surfaces in their natural environment.
- all of the above are functions of these substances.
- to provide motility to the bacterial cells .
Which of the following terms refers to a bacterial cell having a single flagellum at both ends?
- monotrichous
- amphitrichous
- atrichous
- lophotrichous
- peritrichous
- amphitrichous
Proteus mirabilis moves across a surface by rotating flagella. This movement is called
- gliding motility.
- twitching motility.
- swimming.
- swarming.
- conjugative motility.
- swarming.
In nature, antibiotic resistance among pathogenic bacteria can be spread by ____.
- flagella
- fimbria
- pili
- peptidoglycan
- pseudomurein
- pili
In the name E. coli O157:H7, “H7” indicates an antigenic type of _____.
- core polysaccharide in the outer membrane
- flagella
- lipid A
- histone-like proteins
- H antigen
- flagella
E. coli O157:H7, a Gram-negative, has all of the following structures EXCEPT
- lipid A.
- teichoic acid.
- LPS.
- porins.
- O-polysaccharides.
- teichoic acid.
Which of the following places the steps of the Gram stain in the correct order?
1-Alcohol
2-Crystal violet
3-Safranin
4-Iodine
- 1-2-3-4
- 1-3-2-4
- 2-4-1-3
- 4-3-2-1
- 2-1-4-3
- 2-4-1-3
Which is NOT a function of bacterial cell wall?
- to support for fragile cell membrane.
- to transport highly hydrophilic molecules.
- to serve as a point of anchorage for flagella.
- to maintain the bacterial cell shape.
- to contribute to pathogenesis of some pathogenic bacteria.
- to transport highly hydrophilic molecules.
Gram-variables show different gram staining result as the culture ages, probably because
- the peptidoglycan layer gets thicker.
- they increase the volume of periplasm.
- the teichoic acid layer gets thicker.
- the peptidoglycan layer gets thinner.
- the LPS layer gets thinner.
- the peptidoglycan layer gets thinner.
Which part of LPS is responsible for septic shock?
- O polysaccharide
- lipid A
- core polysaccharide
- H antigen
- O antigen
- lipid A
High concentration of _____ in the wall of Mycobacterium tuberculosis is the main reason why the staining of the bacterium requires a special treatment.
- arabinose
- peptidoglycan
- lipoteichoic acid
- carbolfuchsin
- mycolic acid
- mycolic acid
Penicillin kills bacterial cells by
- enhancing lysozyme activity.
- producing less peptidoglycan precursor molecules.
- inhibiting transpeptidase activity.
- inhibiting transglycosylase activity.
- inhibiting lysozyme activity.
- inhibiting transpeptidase activity.
If you treat E. coli (a Gram-negative) with lysozyme inside an isotonic solution for a long time,
- E. coli membrane shrinks.
- E. coli cell is lysed.
- E. coli L-form is produced.
- E. coli protoplast is produced.
- E. coli spheroplast is produced
- E. coli spheroplast is produced
The proton motive force is DIRECTLY responsible for the following functions in the bacterial cell EXCEPT,
- primary active transport
- symport
- ATP production
- antiport
- flagella motility
- primary active transport
The flexibility of bacterial membrane is regulated by
- peptidoglycan.
- polyenes.
- sterols.
- hopanoids.
- cholesterols.
- hopanoids.
Some aquatic microaerophiles use _____ to orient their swimming downward along the magnetic grids of Earth until they reach a suitable attachment site.
- carboxysomes
- magnetosomes
- gas vacuoles
- sulfur granules
- lipid inclusions
- magnetosomes
Endospore formers include species of
- gram-negative bacilli.
- Clostridium.
- Escherichia.
- cyanobacteria.
- All of the above
- Clostridium.
Which is NOT a reason for endospores to have resistance to boiling, UV, chemicals like H2O2, and desiccation?
- formation of only one endospore inside the mother cell.
- Ca2+-dipicolinate.
- Small-acid soluble proteins.
- lack of water.
- All of the above are reasons for the endospore’s resistance.
- formation of only one endospore inside the mother cell.
Louis Pasteur disproved spontaneous generation with the concept of _____ which states that living cells can arise only from preexisting living cells. He demonstrated that microorganisms are present in the air and can contaminate sterile solutions by using a special flask named _____.
biogenesis/swan-neck flask
Pasteur’s solution to the spoilage problem of wine was ______ where beer, milk, and wine are heated just enough to kill most of the bacteria that caused the spoilage.
pasteurization
Koch proved that Bacillus anthracis caused anthrax in cattle by establishing ____, a sequence of experimental steps that directly relate a specific microbe to a specific disease.
Koch’s postulates
The beta-1,4-linkage in peptidoglycan can be degraded by an enzyme named ____ found in tears.
lysozyme
Due to high concentration of a hydrophobic waxy lipid in the cell wall, Mycobacterium tuberculosis must be stained with heating. This staining method is called ______.
acid-fast staining
Streptococcus pneumoniae, a causative bacterium for pneumonia, has a _____ which surrounds the bacterium in an organized manner and firmly attaches to the cell wall. Without this structure, S. pneumoniae becomes avirulent.
capsule
What are the three basic shapes of bacteria? Also, briefly describe at least two variations of each shape.
- coccus (round); diplococcus, streptococcus, staphylococcus…
- bacillus (rod): diplobacillus, streptobacillus…
- spiral: spirillum, spirochete…
Treponema pallidum, a spirochete casing syphilis, uses a special appendage to propel itself.
a) What is the name of this structure?
b) Briefly explain why this structure is more beneficial to the bacterium than flagella.
a) axial filaments or endoflagella
b) better in moving through thick viscous tissue.
Why is the potassium uniport an example of secondary active transport system even though it does not involve the actual co-transport of a proton?
it uses only part of PMF, the electrochemical gradient.
