Module 6A Flashcards
Cultivating Microorganisms
name the 2 contrary types of metabolism
catabolism and anabolism
what is anabolism
- biosynthesis
- it consumes energy
what is catabolism
- the breaking down of chemicals
- it releases energy
what are included in macronutrients
C, N, P, S, O
what are micronutrients
- nutrients only required by some species
what are some examples of common micronutrients
Fe, Cu, Na, Mg, Mn
whare are metabolic categories based on
- energy source
- electron source
- carbon source
what are the 2 energy sources
- chemicals (chemotrophs)
- light (phototrophs)
what are the 2 carbon sources
- heterotrophs, obtained from fixed organic matter
- autotrophs, gaseous inorganic carbon
what are the 2 electron sources
- organotrophs, organic chemicals
- lithotrophs, inorganic chemicals
what are the categories of aerobic organisms
- obligate aerobes: have to use O2
- microaerophiles: requires O2, but at low concentrations
what are the categories of anaerobic organisms
- aerotolerant anaerobe: has no aerobic metabolism, O2 doesn’t affect them
- obligate anaerobe: can’t grow w/ oxygen present
- facultative anaerobe: ferment when O2 is not present, frow faster with O2
what are toxic oxygen species
- unstable oxidizing agents
- remove electrons from cofactors in proteins
- remove electrons from nucleic acids
- harmful to cells that can’t defend themselves
how do antioxidants shield cells against ROS
- they become oxidized themselves
- the get reduced back with things like NADPH
what are the categories of microorganisms in terms of pH
- acidophiles
- neutrophiles
- alkalophiles
what is the calculation for water activity
(volume pressure of air in equilibrium with substance) / (volume pressure of air with pure water)
what is the common water activity value
- most bacteria require > 0.9
- most microorganisms prefer 0.980 - 0.995
how is water loss prevented in a hypertonic environment
- pumping in inorganic ions from the environment
- synthesis/concentration of organic compatible solutes like sucrose or glycerol
how are microorganisms classified in terms of temperature
- hyperthermophiles
- thermophiles
- mesophiles
- psychrophiles
what are some features of hyperthermophiles
- have critical AA substitutions in key locations
- they increase ionic bonding between acidic and basic AA residues
- produce compatible solutes that promote the stability of proteins
what is solid mediums used for
isolating a pure culture into colonies
what are liquid mediums used for
growing microorganisms to high densities and enriching microorganisms in a mixed culture
what are some ways to describe colony morphology
- circular, filamentous, slimy
- other textures and elevations
what is a complex media
the chemical composition is unknown
