BIMM 120 Midterm questions with
verified answers
Why do we study microorganisms? - correct answer ✔✔ Impacts on
1) Disease
2) Agriculture
3) Food
4) Energy/environment
5) Biotechnology
a) acidophiles
b) alkaliphiles
c) halophiles
d) thermophiles
e) psychrophiles
f) piezophiles - correct answer ✔✔ a) acidic pH=0
b) alkaline pH=12
c) high salinity= 32%
d) high temperature=113*C
e) low temperature= -10*C
f) high pressure=1000atm
ARCHAEA
, archaea vs bacteria - correct answer ✔✔ bacteria are pathogenic, photosynthetic, and have
ester-linked membrane lipids, muramic acid in cell wall
archaea can be extremophiles, have histones and txn factors, and ether-linked lipids
prokaryotes vs eukaryotes - correct answer ✔✔ pro: operons, 70S ribosome, introns, no
nucleus, can fix N2
-> less differentiated, fewer organelles, higher energy
euk: no operons, 80S ribosome, no introns, has nucleus, mRNA protection
->larger cells, more organelles/organization
SSU rRNA - correct answer ✔✔ gene sequence used to phylogenetically classify organisms,
trace evolutionary history and divergence
16S in Bacteria/Archaea; 18S in Eukarya
-present in all organisms
-well-conserved
-evolves constant, steady rate
ribotyping - correct answer ✔✔ isolate colony, make pure culture, extract DNA, PCR for 16S
rRNA gene, sequence, alignment, make phylogenetic tree
gram-positive vs gram-negative - correct answer ✔✔ positive: thick layer of peptidoglycan on
outside/cell wall
negative: thin peptidoglycan layer between inner and outer cell membranes (wavy outer
membrane)
verified answers
Why do we study microorganisms? - correct answer ✔✔ Impacts on
1) Disease
2) Agriculture
3) Food
4) Energy/environment
5) Biotechnology
a) acidophiles
b) alkaliphiles
c) halophiles
d) thermophiles
e) psychrophiles
f) piezophiles - correct answer ✔✔ a) acidic pH=0
b) alkaline pH=12
c) high salinity= 32%
d) high temperature=113*C
e) low temperature= -10*C
f) high pressure=1000atm
ARCHAEA
, archaea vs bacteria - correct answer ✔✔ bacteria are pathogenic, photosynthetic, and have
ester-linked membrane lipids, muramic acid in cell wall
archaea can be extremophiles, have histones and txn factors, and ether-linked lipids
prokaryotes vs eukaryotes - correct answer ✔✔ pro: operons, 70S ribosome, introns, no
nucleus, can fix N2
-> less differentiated, fewer organelles, higher energy
euk: no operons, 80S ribosome, no introns, has nucleus, mRNA protection
->larger cells, more organelles/organization
SSU rRNA - correct answer ✔✔ gene sequence used to phylogenetically classify organisms,
trace evolutionary history and divergence
16S in Bacteria/Archaea; 18S in Eukarya
-present in all organisms
-well-conserved
-evolves constant, steady rate
ribotyping - correct answer ✔✔ isolate colony, make pure culture, extract DNA, PCR for 16S
rRNA gene, sequence, alignment, make phylogenetic tree
gram-positive vs gram-negative - correct answer ✔✔ positive: thick layer of peptidoglycan on
outside/cell wall
negative: thin peptidoglycan layer between inner and outer cell membranes (wavy outer
membrane)
