Module 2 Poll and assignment questions Flashcards
You have isolated a new eukaryotic microbe. You analyze its ribosomes and observe two different forms of the ribosome: a 70S and a 80S. What is the best explanation for this observation?
a. The Asgardian theory: eukarya evolved from archaea
b. the endosymbiotic theory: mitochondria and chloroplasts arise from bacteria
c. The spontaneous generation theory: living organisms arise from inorganic matter
d. There is no rational explanation
B
If the pool of ATP is depleted in a cell, what transport system will be affected?
A. antiporter
b. ABC transporter
c. Symporter
d. Group translocation
e. facilitated diffusion
b.
Which is correct about the gram stain?
a. Gram-positive are pink because they have a thin cell wall whereas gram-negative are purple because they have a thick cell wass
b. Gram-positive are p
What is the best explanation for using beta-lactam to treat Chlamydia infection but not Mycoplasma
a. Chlamydia is an extracellular pathogen whereas Mycoplasma is an intracellular pathogen
b. Chlamydia has peptidoglycan whereas peptioglycan is absent in Mycoplasma
c. Chlamydia has an metabolically inactive extracellular form whereas mycoplasma is always intracellular
d. both lack cell walls and beta-lactam cannot be used
b.
Lysozymes are a defense mechanism in animals. What microbe does it target?
a. archaea
b. fungi
c. viruses
d. bacteria
d. Lysozyme cleaves the beta linkage of the specific sugar between NAG and NAM
If you isolate an unknown microbe and biochemical analysis reveals the presence of sugar repeats attached to a lipid integrate into an outer membrane, which type of microbe do you have?
a. Archaea
b. fungi
c. Viruses
d. gram-positive bacteria
e. gram-negative bacter
e.
You want to use an antibiotic that targets the cell wall to treat an infection/ Which group is the most resistant?
a. acid fast bacteria
b. mycoplasma
c. gram-negative bacteria
d. gram-positive bacteria
e. fungi
b. and e.
What structure is universally found in all cellular microbes?
a. the capsule
b. the cytoplasmic membrane
c. the nuclear membrane
d. the outer membrane
e. the S layer
b.
What is the outermost layer of a bacteria?
a. S-layer
b. capsule
c. cell wall
d. mycolic acids
e. outer membrane
f. not enough information to provide an answer
f.
-outer layer of acid fast = mycolic acid
-outer layer gram negative = cell wall
-outer layer of gram positive = outer membrane
A bacteria is described as being hairy when observed under the microscope. What is the structure?
a. Pili
b. LPS
c. Capsule
d. Flagella
A.
You’re favorite bacterium moves, and you did not detect a flagellum. What type of motility is your bacterium most likely capable of?
a. twitching
b. swimming
c. gliding
d. gliding, swimming and twitching
e. no motility
a and c
You want to know if your bacterium is capable of sensing and moving in response to a hydrocarbon gradient. In a chemotaxis assay, your bacterium exhibits motility but moves toward the hydrocarbon. what is the best explanation?
a. HC is an attractant
b. HC is a repellant
c. HC does not induce a chemotaxis response
d. Bacterium is not capable of motility
a.
Select the true statement
a. unicellular eukaryotes are capable of swimming, twitching and gliding
b. Archaea are capable of S, T and G
c. Bacteria are capable of S, T, and G
d. Swimming in bacteria, archaea and unicellular eukaryotes is ATP dependant
c.
Your favorite bacterium is producing a sticky substance when it grows on agar. You have decided to identify the unknown substance. What physical properties would help you differentiate a capsule from a slime layer?
a. The capsule provides a tight matrix that excludes small molecules, whereas the slime layer is loosely packed
b. It is impossible to tell the difference between a capsule and a slime layer as both are always composed of polysaccharides
c. The capsule is a sticky coating made of polysaccharides, whereas the slime layer is a mosaic tile made of proteins
d. The capsule is easily detached from the bacterial cell, whereas the slime layer is strongly attached to the cell
a.
Which of the following is NOT a property of a cell?
a. It performs metabolism and produces energy
b. It is the fundamental component of life
c. It is the basic unit of living organism
d. It arises from pre-existing cells
e. It contains DNA or RNA; never both
e.
You want to know if your bacterium is capable of moving. Which assay(s) will help you measure and/or observe movement? Select all that applies
a. Darkfield microscopy with a viscous liquid medium
b. Brightfield microscopy with a Gram stain
c. By spotting the bacteria on an agar plate and looking for radial migration from the spot
d. Chemotaxis assay using a capillary tubes
a,c,d
Why is it called an ABC transporter?
a. It requires a concentration gradient for transport
b. It requires ATP for energy
c. It is based on a mnemonic devise
d. It requires phosphorylated sugars for energy
b
If the proton motive force is depleted in a bacterial cell, what type of motility will be affected? Select all that apply.
a. The proton motive force is not involved in bacterial motility
b. Gliding
c. Swimming
d. Twitching
b and c
You are trying to prevent the transformation of a spore into a vegetative cell. What step of the sporulation cycle should you inhibit?
a. Germination
b. Engulfment
c. The asymmetrical division
d. Maturation
a
