Practice questions

• the decision to form a biofilm is regulated by quorum sensing
• mesophilic organisms grow in moderate temperatures (15-45 C)
• cytochrome b/c1 is an electron carrier and proton pump
• the starting compounds of lactic fermentation are pyruvate and NADH
• does alcoholic fermentation use pyruvate?

  yes, converted to acetylaldehyde
• NADH reductase accepts electrons from NADH, oxidizing NADH to NAD+
• where in the photosynthetic apparatus is the Fe-S center located?

  e- transport chain
• purple bacteria can grow photosynthetically and aerobically in the dark
• endospores form by asymmetric cell division
• biofilms provide protection but have low motility and access to nutrients
• what type of energy does ATP synthase convert?

  ATP synthase converts mechanical energy to chemical energy
• what part of the cell is ATP synthase in?

  e- transport chain
• what direction is the proton gradient formed in e- transport?

  protons are pumped into environment
• what process is cheese made by?

  lactic acid fermentation
• what molecules require nitrogen?

  amino acids, nucleic acids, and peptidoglycan
• where are inclusions (nutrient storage) found?

  in the cytoplasm
• what does viable plate count measure?

  live bacteria (colonies)
• what type of growth control is pasteurization?

  sanitation
• what are e- sources for purple bacteria (anoxygenic photosynthesis)?

  H2S, H2 or organic acids
• aerotolerant anaerobes are facultative
• what temperature do autoclaves get to?

  121 C
• what temperature do dry ovens get to?

  160-170
• what is the function of Fe-S centers?

  e- carriers
• which half reaction do you flip when calculation change in potential?

  the donor (more -)
• how does alcohol sterilize?

  preservative, produced by yeast
• lithotroph: inorganic e- source
• what was retinal-based phototrophy first discovered in?

  halophilic archaea
• what single proteins does retinal-based phototrophy use?

  bacteriarhodopsin
• Keq is products/reactants, less than 1 favors forward reaction
• chlorosome is the light harvesting pigment in green bacteria
• core and peripheral are the light harvesting complexes in purple bacteria
• phycobiliproteins are the light harvesting proteins in cyanobacteria
• what is the function of the proteins in light harvesting complexes?

  hold pigments close to the outside of the cell
• what is a carotenoid and where is it found?

  pigment, light harvesting complex and reaction center
• what is used as co-factors/co-enzymes?

  trace elements
• what are inorganic e- sources?

  H2O and H2S
• what are organic e- sources?

  succinate and fructose
• biocides modify and denature DNA, proteins, and what other impact?

  disolve and disrupt membranes
• quinones are found in the reaction center and e- transport chain of all 3 bacteria groups
• Fe-S center is found in the e- transport chain of all 3 bacteria groups