Principles of Micro 4 Flashcards
what are the two types of cell inclusions in bacteria
glycogen and polyphosphate
where are the cell inclusion found and what are their functions
glycogen: found in many species, carbon and energy storage
polyphosphate: found in many species, phosphate storage
are endospores mainly gram pos or gram neg
main gram pos
just recently found one gram neg one
what is the importance of endospores
they shut down protein, enzymatic, and macromolecular synthesis and wait
they are important for heat, chemical, and radiation resistance for bacteria
what are the three locations for bacterial cell in endospores
terminal - all the way to one end
central - in the middle
subterminal - almost all the way to one end
name the endospore formers
c. difficile
c. botulinum
c. tetani
b. cereus
what is so important about c. difficile
significant for infection control
describe sporulation and germination
in harsh environment, bacteria cells undergoes sporulation where it replicates and produces a spore while the original cell dies (take 6-8hrs)
then in favorable environment, the spore germinates back to bacteria taking 1 - 2 hrs
what are components that influence growth of microorganism
temperature, pH, water, carbon and energy sources, trace elements
how does temperature influence growth rate of microorganism
there is an optimum range for microorganism growth
also there is a min and max temp where microorganism do not grow
name the temperature categories in which microorganisms fall under; what the optimum temp is in degree celsius; and if medically significant
psychrotrophs and psychrophiles - 15 oC - No
Mesophiles - 20-40 oC - Yes
thermophiles - 50-60 oC - No
what is the difference between pyschrotrophs and psychrophiles
psychrophiles are cold loving and actually handle temperatures as low as 2 - 3 oC while psychrotrophs can tolerate the cold weather so their optimum is only 15 oC
random pop quiz: what is a firmly attached polysaccharide layer that is located external to the cell wall/outer membrane which enables bacterial evasion one of the host non specific defenses
capsule
list the pH categories in which microorganisms fall under and what pH they can handle
extreme acidophiles: 0-2 acidophiles: 3 - 5 neutrophiles: 6 -8 alkalophiles: 9 - 11 extreme alkalophiles: 12-14
list the ranges of water availability in which microorganisms can thrive/not thrive
.93 - .98: no growth of gram positive bacteria
.97 - no growth of gram neg bacteria
less than .93 - most spoilage due to yeast and fungi
less than .9 - most bacterial unable to grow
less than .6 - no microbial growth
what do all organisms need
carbon and energy source
what are way in which organisms can get energy
chemotrophs - chemical energy
phototrophs - light energy
examples of phototrophs
plants, algae, photosynthetic bacteria
what are two types of chemotrophs
chemolithotrophs - use inorganic sources of carbon
chemoorganotrophs (heterotrophs) - use organic sources of carbon (most bacteria)
examples of chemoorganotrophs aka heterotrophs
bacteria, fungi, protozoa, humans