eating habits - 12th set Flashcards
(151 cards)
Inoculum
the starting culture. term used when microbes are introduced into a medium
(i.e. rich nutrient source ) to initiate growth
Culture (newport)
growth of microorganism in a culture medium.
Growth (divide)
refers to microbial multiplication; increase in number (or population) i.e. bacterial division not bacterial size
Culture medium (lab only)
defined as nutrient material prepared for growth of microorganism in lab. bacteria growing in nature are not growing in culture medium. culture only in lab.
Pure culture (adopt)
descendants of a single cell and separated from others
Bacterial growth may result either in…(US)
a colony or a biofilm
Colony (kenny)
aggregation of cells arising from a single parent cell
Biofilm (bugs on water - malaria)
collection (many different species of microbes) of surface microbes living in a complex community. it amplifies disease causing ability of bacteria if they’re in a biofilm community
pure colony
when all cells are of the same type, no contamination.
Criteria for culture medium - it must contain (cooking)
appropriate nutrients in proper proportion for the specific microorganism
growth requirements - physical factors (PLOOT)
temperature, ph, light (energy source), osmosis and osmotic pressure
nutrient uptake - passive process (diffusion) (ex)
= downhill movement
- substance movement is from a region of high concentration to low concentration
- NO expenditure of cellular energy - simple diffusion, facilitated diffusion, osmosis
nutrient uptake - active process (group bacteria - desert - bus tour) it includes…
= uphill process - functions when bacteria are in low nutrient environment there is expenditure of cellular energy. includes
active transport and group translocation
Simple diffusion and ex. (think small)
- small or lipid soluble substances easily moves down concentration gradient across plasma membrane. - movement continues until equilibrium is reached between inside and outside. Ex: oxygen, co2, water, short chain/small fatty acids
Facilitated diffusion and ex. (GUV)
used by molecules unable to diffuse or fails to dissolve across lipid bilayer - use channel proteins Ex: glycerol, urea, vitamins
Difference between simple and facilitated diffusion? (shuttle - rainy day)
- carrier requirement,
- facilitated diffusion is a saturable process unlike simple. saturable process is when all binding sites are used up, it will come to a standstill. (shuttle) channel proteins are like revolving doors.
Active transport (front door - jonathan - buf)
involves substance movement from outside to inside, i.e. against concentration gradient (uphill) - substance that cross membrane is not altered. no chemical alteration of molecule
group translocation (group mail thieves)
cells picks substance even though they are in lower concentration outside than inside- substance altered during transport; prevents from leaving the cell.
group translocation process (group photo of pony)
glucose utilization by the phosphotransferase system, purines, pyrimidines and long chain fatty acids transport
Minimum growth temperature (no more)
lowest temperature at which species will grow; slow metabolism - any lower and it’s too slow to support metabolic activities of the cell.
Optimum growth temperature
species grows best at this temperature; fastest growth because all metabolic reactions are supported well at this temperature.
Maximum growth temperature (lowest and highest - body temp)
highest temperature at which growth is possible, though slow growth. beyond this temperature, cell dies. below 4 degrees C, bacteria cell will die. at 37 degrees about will grow best.
temperature has an impact on both (protein bar)
proteins and lipids.
proteins: high and low temps (H - kitchen table - H - freezer)
h2 and covalent bonds of proteins are broken. irreversible damage. low temp - h2 bonds are formed, and it disrupts the 3 dimensional shape of the protein.