©SIRJOEL EXAM SOLUTIONS
10/3/2024 9:54 PM
Brock Biology of Microorganisms Chapter 2
Exam Study Guide.
Morphology - answer✔cell shape
coccus - answer✔spherical or ovoid shape
bacillus - answer✔rod or cylindrical shape
spirillum - answer✔curved or spiral shape
spirochetes - answer✔tightly coiled shape, appendaged bacteria, and filamentous bacteria
(includes budding bacteria)
size range for most prokaryotes - answer✔-0.2-->700 micrometers in diameter
-largest is Thiomargarita namibiensis
size range for eukaryotes - answer✔-2->>600 micrometers in diameter
advantages to being small - answer✔-larger surface area to cell volume ratio
-grow faster
-evolve faster
ultramicrobacteria - answer✔bacteria between 0.2-0.4 micrometers in diameter with highly
streamlined genomes
bacterial cytoplasmic membrane - answer✔-membrane that is more like a matrix instead of a
completely fixed structure (very fluid/dynamic)
-have phospholipid bilayer w/proteins
hopanoids - answer✔sterol-like molecules that help strengthen some bacterial cell walls
archaeal membranes - answer✔-have ether linkages in phospholipids of archaea (in contrast to
ester links)
, ©SIRJOEL EXAM SOLUTIONS
10/3/2024 9:54 PM
-lipids have isoprenes, not fatty acids
-some only have monolayer if lipids (not bilayer, especially in thermophilic)
bacterial cell walls - answer✔-these walls have peptidoglycan
mycoplasms - answer✔pathogenic bacteria related to gram-positive bacteria, but do not have cell
walls
thermoplasmas - answer✔archaea that do not have cell walls
archaeal cell walls - answer✔-these walls do not have peptidoglycan
-many, but not all, have pseudomurein
pseudomurein - answer✔substance found in cell walls of certain methanogenic archaea;
polysaccharide similar to peptidoglycan
-penicillin and lysozyme would not work on these
capsules and slime layers - answer✔-assist in surface attachment
-develop and maintain biofilms
-protect against phagocytosis
-prevent dehydration/dessication
fimbriae and pili - answer✔-filamentous protein structures
-help organisms stick to surfaces or form pellicles
hamus/hami - answer✔-archaeal "grappling hooks" help surface attachment, forming biofilms
-resemble pili except for barbed terminus
cell inclusions - answer✔not a true organelle, but help cells save materials for later if able
-energy reserves
-carbon reserves
-enclosed by thin membrane
-reduce osmotic stress
gas vesicles - answer✔-confer buoyancy in planktonic cells
-conical-shaped, gas-filled structures made of protein
10/3/2024 9:54 PM
Brock Biology of Microorganisms Chapter 2
Exam Study Guide.
Morphology - answer✔cell shape
coccus - answer✔spherical or ovoid shape
bacillus - answer✔rod or cylindrical shape
spirillum - answer✔curved or spiral shape
spirochetes - answer✔tightly coiled shape, appendaged bacteria, and filamentous bacteria
(includes budding bacteria)
size range for most prokaryotes - answer✔-0.2-->700 micrometers in diameter
-largest is Thiomargarita namibiensis
size range for eukaryotes - answer✔-2->>600 micrometers in diameter
advantages to being small - answer✔-larger surface area to cell volume ratio
-grow faster
-evolve faster
ultramicrobacteria - answer✔bacteria between 0.2-0.4 micrometers in diameter with highly
streamlined genomes
bacterial cytoplasmic membrane - answer✔-membrane that is more like a matrix instead of a
completely fixed structure (very fluid/dynamic)
-have phospholipid bilayer w/proteins
hopanoids - answer✔sterol-like molecules that help strengthen some bacterial cell walls
archaeal membranes - answer✔-have ether linkages in phospholipids of archaea (in contrast to
ester links)
, ©SIRJOEL EXAM SOLUTIONS
10/3/2024 9:54 PM
-lipids have isoprenes, not fatty acids
-some only have monolayer if lipids (not bilayer, especially in thermophilic)
bacterial cell walls - answer✔-these walls have peptidoglycan
mycoplasms - answer✔pathogenic bacteria related to gram-positive bacteria, but do not have cell
walls
thermoplasmas - answer✔archaea that do not have cell walls
archaeal cell walls - answer✔-these walls do not have peptidoglycan
-many, but not all, have pseudomurein
pseudomurein - answer✔substance found in cell walls of certain methanogenic archaea;
polysaccharide similar to peptidoglycan
-penicillin and lysozyme would not work on these
capsules and slime layers - answer✔-assist in surface attachment
-develop and maintain biofilms
-protect against phagocytosis
-prevent dehydration/dessication
fimbriae and pili - answer✔-filamentous protein structures
-help organisms stick to surfaces or form pellicles
hamus/hami - answer✔-archaeal "grappling hooks" help surface attachment, forming biofilms
-resemble pili except for barbed terminus
cell inclusions - answer✔not a true organelle, but help cells save materials for later if able
-energy reserves
-carbon reserves
-enclosed by thin membrane
-reduce osmotic stress
gas vesicles - answer✔-confer buoyancy in planktonic cells
-conical-shaped, gas-filled structures made of protein
