©THEBRIGHT 2024
Micr 221 Exam Questions With Correct
Answers
Aerobic environment and aerobes environment - answer✔✔high oxygen (atmospheric, 21% O2)
oxic environment
Microaerobic environment and microaerophiles environment - answer✔✔trace oxygen (2-10%
O2 or less)
hypoxic environments
Anaerobic envirnment and anaerobes environment - answer✔✔strictly 0% O2
anoxic Environment
facultative - answer✔✔if O2 is present it will use, if not then it won't use O2
Flexibility - answer✔✔ability to adapt to a range of environments
Higher eukaryotes flexibility and why - answer✔✔inflexible
- obligately heterotrophic
- obligately aerobic (respiration)
bacteria flexibility and why - answer✔✔highly flexible
- diverse organic and inorganic e- donors
- O2 and anaearobic e- acceptors (facultative)
r type strategist definition and example - answer✔✔fast growing (TD=mins)
use food wastefully
E.coli, B.subtilis
K type strategist definition and example - answer✔✔slow growing (TD=days)
use food efficiently
M. tuberculosis
, ©THEBRIGHT 2024
Persisters - answer✔✔the cells that remain after antibiotics
At what stage does antibiotics no longer kill a cell - answer✔✔stationary phase, cell wall isn't
turning over
Antibiotic resistance - answer✔✔heritable, genetic changes allow bacteria to grow
Antibiotic persistence - answer✔✔non heritable, physiological changes allow survival of a few
slow or non growing cells
Hypoxia - answer✔✔gradual depletion of oxygen leads to a stationary phase, slowed growth and
persistent phenotype
Triggers of persistence - answer✔✔- run out of nutrients (becomes non replicating)
- oxygen deprivation
bacterial cells need to be able to generate... - answer✔✔energy source, carbon source, reducing
power
Intergral membrane proteins - answer✔✔proteins that spam the lipid bilayer
has a specific function
amphipathic protein structure - answer✔✔- hydrophobic and hydrophilic regions
- hydrophobic regions interact with lipids
- hydrophilic regions = core of protein
Classes of bacterial active transporters - answer✔✔1) major facilitator (MFS)
2) ATP binding cassette (ABC) superfamily
3) groups translocation: phosphoenolpyruvate dependent phosphotranferase system (PTS)
3 types of MFS - answer✔✔Uniporter
antiporter
symporter
ABC function - answer✔✔exporter (drug pumps)
importers (solute uptake)
advantages of active transport - answer✔✔1) more competitive for scarce resources
2) rapid response to fluctuating environment
Micr 221 Exam Questions With Correct
Answers
Aerobic environment and aerobes environment - answer✔✔high oxygen (atmospheric, 21% O2)
oxic environment
Microaerobic environment and microaerophiles environment - answer✔✔trace oxygen (2-10%
O2 or less)
hypoxic environments
Anaerobic envirnment and anaerobes environment - answer✔✔strictly 0% O2
anoxic Environment
facultative - answer✔✔if O2 is present it will use, if not then it won't use O2
Flexibility - answer✔✔ability to adapt to a range of environments
Higher eukaryotes flexibility and why - answer✔✔inflexible
- obligately heterotrophic
- obligately aerobic (respiration)
bacteria flexibility and why - answer✔✔highly flexible
- diverse organic and inorganic e- donors
- O2 and anaearobic e- acceptors (facultative)
r type strategist definition and example - answer✔✔fast growing (TD=mins)
use food wastefully
E.coli, B.subtilis
K type strategist definition and example - answer✔✔slow growing (TD=days)
use food efficiently
M. tuberculosis
, ©THEBRIGHT 2024
Persisters - answer✔✔the cells that remain after antibiotics
At what stage does antibiotics no longer kill a cell - answer✔✔stationary phase, cell wall isn't
turning over
Antibiotic resistance - answer✔✔heritable, genetic changes allow bacteria to grow
Antibiotic persistence - answer✔✔non heritable, physiological changes allow survival of a few
slow or non growing cells
Hypoxia - answer✔✔gradual depletion of oxygen leads to a stationary phase, slowed growth and
persistent phenotype
Triggers of persistence - answer✔✔- run out of nutrients (becomes non replicating)
- oxygen deprivation
bacterial cells need to be able to generate... - answer✔✔energy source, carbon source, reducing
power
Intergral membrane proteins - answer✔✔proteins that spam the lipid bilayer
has a specific function
amphipathic protein structure - answer✔✔- hydrophobic and hydrophilic regions
- hydrophobic regions interact with lipids
- hydrophilic regions = core of protein
Classes of bacterial active transporters - answer✔✔1) major facilitator (MFS)
2) ATP binding cassette (ABC) superfamily
3) groups translocation: phosphoenolpyruvate dependent phosphotranferase system (PTS)
3 types of MFS - answer✔✔Uniporter
antiporter
symporter
ABC function - answer✔✔exporter (drug pumps)
importers (solute uptake)
advantages of active transport - answer✔✔1) more competitive for scarce resources
2) rapid response to fluctuating environment
