1What defines microbial growth?
*increase in # of cells, by cellular division/fission
2What does microbial growth refer too?
*increase in the number of cells not cell size
3What are permissive conditions?
*minimum and maximum thresholds where cells survive
4What are optimum conditions?
*the ideal conditions that facilitate mass cell growth
5What are the physical growth requirments of microbes?
*temperature
*pH
*osmotic pressure
*light/energy
6What are the chemical requirments of microbes?
*C, N, S, P, O, H, salts and trace elements
7What growth factors are needed by microbes?
*vitamins, amino acids
8What are mesophiles? What temp's do they thrive at?
*live with us (under normal conditions)
*between 10-50 degrees C
9What are psychotrops? What temp's do they thrive at?
*can grow in fridge
*optimized at normal room temp
*able to grow from 0-30 degrees C
10What are psychrophilles? What temp's do they thrive at?
*live in ice bergs
*grow between -10 to 20 degrees C
11What are hyperthermophiles? What temp's do they thrive at?
*live in thermal vents
*grow between 60-110 degrees C
12What are Thermophiles? What temp's do they thrive at?
*live in hot tubs
*grow between 40-75 degrees C
13What temperature do proteins work best in humans (most of the time)?
*37 degrees C
14What types of bonds keep enzymes together in high temperature environments?
*disulfide bonds
15What temperature zone leads to rapid growth of bacteria in C and F?
*20-50 C
*60-130 F
16What is the ph range of our cells?
*intracellular ph is 6-8
17What bacteria function in ph range of 0-5?
Acididophiles
18What bacteria function in ph range of 5-8?
*Neutraphiles
19What bacteria function in ph range of 9-11?
Alkaliphiles
20What ph do molds and yeast grow at?
5 and 6
21Describe plasmolysis, what causes it?
*plasmolysis= cell wall is rigid but bacteria shrivels up within
*caused by a hypertonic environment (lots of salt or sugar) leads to water leaving cell
22What type of bacteria require high osmotic pressure?
*extreme halophiles
*obligate halophiles (need high salt environment)
23What are halophiles?
*bacteria that can survive in areas with high salinity (salt concentration)
24What type of bacteria tolerate high osmotic pressure?
*Facultative halophiles
25what is crenation?
wrinkling up
26What type of bacteria is Cyanobacterium B. spirulina?
*autotrophic (uses sun to fix carbon)
*gram negative bacteria
*turns water and flamingos pink
27Use of carbon by bacteria?
energy source
28Use of nitrogen by bacteria? builds what to make what
amino acids (proteins)
nucleotides (nucleic acids)
29How do most bacteria get their requirement of nitrogen?
decompose proteins as source
30Use of sulfur by bacteria? Source of sulfur?
in amino acids (thiamine, biotin)
most get sulfur from decomposing proteins
31Use of phosphorus by bacteria?
*DNA (phosphodiester backbone), RNA, ATP, and membranes (phosphate is the source) PO4 -3
32What are two main routes of carbon aquistion by bacteria?
*Heterotropy (energy from C-H molecules)
*Autotrophy (carbon fixation, via phototrophy or lithotrophy)
phototrophy uses photosynthetic pigments
(lithotrophy uses metals?
33Auto meaning with carbon source?
CO2 is fixed and assembled into organic molecules
34Hetero meaning with carbon source?
*preformed organic molecules are acquired from outside cell and broken down for carbon, carbon then reassembled into biomass
35Photo meaning with energy source?
*light absorption captures energy
36Chemo meaning as an energy source?
preformed organic or inorganic electron donors are oxidized
37Meaning of Litho (electron source)
*inorganic molecules donate electrons
38Meaning of Organo (electron source)
*organic molecules donate electrons
39What type of nitrogen is required for biosynthesis?
*reduced nitrogen (NH3) (NH4+)
40What is nitrogen fixation?
*reduction (N2 converted to NH4+)
41What is nitrification?
conversion of NH4+ into NO3 - (nitrate)
42What is nitrate reduction?
*NO3- into NH4+
nitrate into ammonia
43What is denitrification?
*NO- into N2
nitric oxide to nitrogen
44Why are trace elements needed?
*enzyme cofactors
45Oxygen requirments of strict aerobes?
*require oxygen for energy metabolism
*they detoxify reactive oxygen
*survive only in environments with oxygen
46Oxygen requirments of anaerobes?
*do not require oxygen for energy metabolism
*generally unable to detoxify reactive oxygen species (ROS)
*survives only in oxygen free environments
47Which organism undergoes oxidative phosphorylation aerobes or anaerobes?
aerobes (need O2)
48What type of electron receptors do anaerobes use?
*some use metals
*other receptors besides oxygen
49What are the four toxic forms of oxygen?
*Singlet oxygen
*superoxide
*peroxide anion
*hydroxyl radical
50What is a singlet oxygen?
*O2 boosted to a higher energy state
51What is a superoxide?
*free radicals of O2-
52What is a peroxide anion?
O2 -2
53What are two examples of ROS (reactive oxygen species)
*catalase
*peroxidase
54How do we now if ROS catalase is working?
*bubble formation from O2
55What does a hydroxyl radical look like?
*OH
56What two enzymes allow bacteria to survive in oxygen rich enviornment? (toxic forms of O2)
*catalase and peroxidase
57What type of bacterium is Cholesterium histolyticum?
*mobile bacterium
*doesn't need O2
58What culture method is used from anaerobic bacteria?
*Anaerobic jar with envelope (contains sodium bicarbonate and sodium borohydride)
*packet pulls out O2 and releases Co2 and H20 into jar keep it moist and happy
59What is the oxygen requirement of microaerophille?
*need certain amount of O2
60What is reducing media?
*contains chemicals that bind to oxygen resulting in an oxygen gradient
*thioglycollate or oxyrase
61What does thioglycollate or oxyrase do?
*binds to oxygen resulting in oxygen gradient within container
62Why is the thioglycollate broth red at parts and yellow at others?
*red (has dye) when oxidized
*yellow (no oxygen)