Microbial Growth
What is microbial growth?
an increase in number of cells, not cell size
Sepsis
Define enzyme
Define aerobic respiration
Oxygen is the final electron acceptor
What does the inhibitor bind/bond to during noncompetitive inhibition?
Allosteric site
Define Psychrophiles, Mesophiles, and Thermophiles.
Give optimal temperatures of each.
Psychrophiles = cold loving ~ 10-15 degrees C
Mesophiles = moderate loving ~ 37 degrees C
Thermophiles = heat loving ~ 55 degrees C and above
What is removal of pathogens from living tissue?
What is removal of pathogens from inanimate objects?
Antisepsis
Disinfection
How does an enzyme function?
It binds to substate at the active site, creates the E-S complex, transforms substrate into product, releases product. It is unchanged and free.
Define phototroph & autotroph
Uses light energy
uses inorganic carbon sources
What are the organisms called that use inorganic carbon sources and those that use organic carbon sources?
Autotroph = inorganic C
Heterotroph = organic C
Define Acidophile, Neutrophile & Alkaliphile
Acidophile - acid loving, grows optimally in acid env
Neutrophile - neutral loving, grows optimally at 7
Alkaliphile - basic loving, grows optimally in basic env
What does the disk diffusion method measure to evaluate a chemical?
Zone of inhibition
What three factors affect enzyme activity?
Temperature
pH
substate concentration
Give the first 3 intermediates in glycolysis
Glucose, glucose 6-P, fructose 6-p, fructose 1,6 diphosphate
What are the requirements for microbial growth?
physical = the environment
chemical = provided by environment
Explain the different forms of toxic oxygen and enzymes to combat them.
Superoxide free radicals, O2- which are neutralized by superoxide dismutase into H2O2.
H2O2 is neutralized by
catalase into H2O + O2
peroxidase into H2O
What reduces spoilage organisms and pathogens with the application of high heat for a short time?
Explain equivalent treatments
Pasteurization
Inverse relationship:
Higher the temps ==> the lower the amount of time
What is a Holoenzyme and what is it composed of?
Protein - Apoenzyme
nonprotein - cofactor/coenzyme
What is the final electron acceptor in lactic acid fermentation? What is the end product?
pyruvic acid receives the electron, hydrogen and becomes lactic acid
When using turbidity to estimate bacterial #/count, what can be summarized about the relationship of absorbance of light and the bacterial #/count?
Higher the absorbance ==> lower population/#
Lower the absorbance ==> higher the population/#
Define generation time & explain the process of binary fission:
Generation time is the time required for a cell to divide or a population to double.
Bacterial chromosome is copied and attached to plasma membrane. Cell elongates and then a cross wall is produced by making more plasma membrane & cell wall. Cell separates into 2 clones.
Give the four physical methods of microbial control:
Temperature, Filtration, Desication/Osmotic pressure, & Radiation
How does an enzyme catalyze a reaction?
Define turnover number:
What do enzymes end in?
By lowering the activation energy of the reaction
the maximum number of substrate an enzyme converts to product each second.
-ase
Explain the electron transport chain
NADH, FADH2 become oxidized.
Carrier protein becomes reduced, series of redox of carrier proteins releases energy & pumps H+ across membrane to create gradient. H+ flows down gradient through ATP synthase releasing energy and ATP is produced. Oxygen is the final electron acceptor creating water.
List & explain the types of phosphorylation:
Oxidative phosphorylation = make ATP during ETC
Substrate level phosphorylation = make ATP by intermediate giving energy and P to ADP during rxn.
Photophosphorylaton = make ATP during photosynthesis