unit 1 clicker questions

Question 1

which statement among a-e is false?

a. microbes are ubiquitous
b. microbes in/on our bodies outnumber our own cells
c. marine microbes supply 5% of the earth’s O2
d. microbes take in >90% of nitrogen from earths atmosphere
e. barely 0.1% of microbes on earth are able to be grown in the lab
f. none are false

Answer 1

c.

Question 2

which statement among a-c is false?

a. archaea is a type of unicellular eukaryote often found in extreme conditions
b. there are two taxonomically different groups (domains) of prokaryotes
c. all microbes containing a nucleus would be found in domain eukarya
d. none are false

Answer 2

a.

Question 3

what is NOT a reason why prokaryotes are so highly adaptable?

a. they grow fast
b. they have diverse metabolic capabilities
c. they mutate at higher rates
d. they can carry out sexual reproduction
e. they have small genomes and a small size
f. they can transfer genes among themselves
g. they can carry out transcription and translation at the same time
h. all are reasons they’re highly adaptable

Answer 3

d.

Question 4

which statement among a-f is true?

a. pasteur’s germ theory of fermentation explains the nature of infectious disease
b. ecologically speaking, you are considered a producer
c. archaea = simplest of the eukaryotic microbes
d. the common cold is considered an EID
e, handwashing with soap=disinfection
f. vaccines work by stimulating your body to produce antigens
g. none are true

Answer 4

g

Question 5

which sentence below is correct?

a. “the nurse sterilized my arm before i receive the vaccination”
b. “the nurse disinfected my arm before i receive the vaccination:
c. neither a or b are correct
d. both a and b are correct

Answer 5

c

Question 6

what bacteria type would use H2S for energy?

Answer 6

lithotropic (inorganic energy source)

Question 7

(prokaryotic cell features) which is false?

a. ether-linked lipids: found in some archaea
b. gram-negatived bacterium: more sensitive to increased osmotic pressure than a gram positive bacterium
c. water: most abundant molecule in a bacterial cell
d. bacterial cell envelope: may or may not include an outer membrane
e. ion gradients: can serve as storage of potential energy
f. capsule: often a virulence factor for those that have it
g. representation of gram negative coccus (not a gram stain)
h. none are false

Answer 7

h.

Question 8

An aquatic bacterium maintains an
intracellular sodium ion concentration of 0.1 mM while living in
a pond that contains sodium
ions at 0.005 mM. Evidently,
sodium ions are entering the cell by:

a. facilitated diffusion
b. pinocytosis
c. osmosis
d, simple diffusion
e. none of the above

Answer 8

e

Question 9

which of a-d is false?

A. Slime layer: gene‐encoded product tightly bound to
the exterior of the cell
B. Haploid = bacteria
C. Virulence factor: fimbriae or capsule could be one
D. Axial filament, pili, flagellum: all could be involved in
bacterial cell motion
E. None of A ‐ D is false; all are true

Answer 9

a

Question 10

among which is true?

A. Mycobacteria species: lack peptidoglycan.
B. Gram‐negative bacteria: have an extra outer membrane.
C. Teichoic acids: found only in a Gram (‒) cell wall.
D. O polysaccharide (O antigen): only associated with a
Gram (+) bacterium
E. Representation of Gram positive coccus 
(this is not a Gram stain)
F. None of A‐E is true.

Answer 10

f.

Question 11

what provides the “selective permeability” of a membrane?

Answer 11

phospholipid

Question 12

the false statement is…

A. Energy is required to produce ATPs.
B. Generally the food that you eat will ultimately become oxidized
by the cells in your body.
C. There are reactions in your body that do not require air
(oxygen).
D. You ate a doughnut this morning. Your body generally sees this
as a source of electrons.
E. ATPs can be used to provide energy for cellular processes.
F. The oxygen you inhale is converted to water.
G. None of A – F is false

Answer 12

g

Question 13

chemical “x” has been oxidized by chemical “z”; this means that …

A. Oxygen has been added to “X”
B. “Z” has lost electrons
C. “Z” has become reduced
D. “X” has gained electrons
E. Two of the above are correct
F. Three of the above are correct

Answer 13

c

Question 14

Respiration does not require…

A. A membrane.
B. An electron transport system.
C. A proton motive force
D. ATP synthase (ATPase)
E. An electron donor
F. All are required

Answer 14

f

Question 15

Fermentation…

A. generally relies on glycolysis to supply ATPs.
B. relies on oxidative phosphorylation for energy production.
C. utilizes an ATPase (ATP synthase).
D. requires oxygen.
E. includes reaction(s) that re‐supply NAD+.
F. Two of A ‐ E are true.

Answer 15

f

Question 16

Which is statement is true?

A. Phototrophs that are anyoxygenic do not use water as an
electron source.
B. Oxygen becomes reduced during oxygenic photosynthesis.
C. CO2 becomes oxidized during CO2 fixation in the Calvin cycle.
D. Photosystem I is linked to photophosphorylation.
E. All phototrophs possess both Photosystem I and Photosystem II.
F. All of A‐E are true.
G. None of A‐E is true

Answer 16

a

Question 17

What would the three bacterial types described below all have in common with respect to the given
characteristics?

Type 1: a psychrophilic, alkalophilic, facultative anaerobe
Type 2: a thermophilic, halophilic, aerotolerant anaerobe
Type 3: a hyperthermophilic, acidophilic, obligate anaerobe

A. They would all be capable of growing in the presence of O2.
B. They would all be capable of growing at temperatures >50°C.
C. They would all grow well in high salt conditions.
D. They would all grow well at acidic pH.
E. None of A ‐D is true.

Answer 17

e

Question 18

A halophilic bacterium would likely be living in
an external environment that is _________with
respect to its’ intracellular environment.

A. hypotonic
B. isotonic
C. hypertonic

Answer 18

c

Question 19

Phosphate is a macronutrient
requirement for life. It is found in:

A. all nucleic acids
B. all proteins
C. all carbohydrates
D. all lipids

Answer 19

b?

Question 20

For most bacteria, increasing the amount of this nutrient to a growth medium will typically lead to a significant increase in cell yield. Which nutrient
would this be?

A. nitrogen
B. carbon
C. sulfur
D. phosphorous
E. iron

Answer 20

b

Question 21

what has the
least amount of SOD, catalase, and/or peroxidase?

Answer 21

obligate anaerobic (no protection from toxic oxygen)

Question 22

What is the carbon and nitrogen source in nutrient agar?

Answer 22

both are peptone and beef extract

Question 23

Would it be possible to obtain a pure culture
isolate from an environmental sample using only flasks of liquid media?

A. Yes B. No C. Maybe

Answer 23

b

Question 24

A bacterial batch growth curve is shown.
Which of the following among A‐D is false?

A. Changes in cell size occur during phases 2 and 3
B. Exponential changes in
cell numbers occur during
phases 2 and 4
C. Acclimation phase = 1
D.Most likely to begin forming
endospores: phase 3
E. None of A – D is false.

Answer 24

e

Question 25

A surface and the ability to attach are absolute
requirements for …

A. Log phase
B. Endospore formation
C. Biofilm formation
D. Lag phase
E. None of the above

For this reason, biofilm forming bacteria must have:

a. cell wall
b. pilli/fimbriae
c. LPS layer
d. capsule
e. starch granules

Answer 25

c and b