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During cellular respiration, how many ATP are made total? Where do those come from?
38 ATP per glucose - 2 from glycolysis, 2 from krebs cycle, 34 from oxidative phosphorylation
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How many ATP are made during oxidative phosphorylation? How many from NADH? How many from FADH?
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What do aerobic and anaerobic respiration have in common?
they both use glycolysis, the Krebs cycle, and oxidative phosphorylation
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What is the final electron acceptor in anaerobic respiration?
an inorganic molecule, like nitrate, sulfate, or carbonate
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Why would some species use both aerobic and anaerobic respiration?
Lack or excess of oxygen
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If a species can't use any form of respiration, what do they use?
fermentation
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molds use what form of respiration?
aerobic
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What species can do all three types of respiration?
E. coli
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what does fermentation use?
glycolysis - but not the krebs cycle or oxidative phosphorylation
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Fermentation does not require...? Making it what form of respiration?
oxygen - anaerobic
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Why is ATP production limited in fermentation?
only 2 ATP are made from the glycolysis
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During lactic fermentation... the pyruvate produced...?
is converted back to lactic acid (NADH converted to NAD+ to accept more electrons)
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What is an example of lactic acid fermentation?
Lactobacillus
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What does lactobacillus make?
yogurt and cheese
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During alcoholic fermentation... the pyruvate...?
is converted to carbon dioxide and ethanol
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What is an example of a bacteria that uses alcoholic fermentation? What does it make?
Saccharomyces cervisiae - bread, wine, beer
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What are some other useful fermentative organisms?
Propionibacterium freundenreichii - swiss cheese
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How many ATP are produced during aerobic respiration?
3
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How many ATP are produced during anaerobic respiration?
38
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How many ATP are produced during fermentation?
2
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Where does photosynthesis occur in bacteria?
folds of the cell membrane (thylakoids of the cyanobacteria)
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Where does photosynthesis occur in plants and algae?
choloroplasts
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What are the two major groups of photosynthetic bacteria?
cyanobacteria & purple and green bacteria
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Where are cyanobacteria found?
wherever sunlight is available, where it's moist - waters, soils, plants
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Where are purple and green bacteria found?
they are senstive to oxygen, so they're found in bodies of water at a deep depth where they is light but no oxygen
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The photosynthesis of cyanobacteria is similar to what?
photosynthesis in eukaryotes
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What two stages do photosynthesis occur in?
light reactions & the Krebs cycle
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What do light reactions do in photosyntheiss?
convert energy in light to chemical energy (ATP, NADPH) and produce oxygen as a waste product - light is captured by pigments
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What is the electron carrier during photosynthesis?
NADPH
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When is oxygen produced during light reactions?
When water is broken down to provide electrons
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What does the Calvin Cycle use? To produce what?
Carbon dioxide and energy - glucose
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What is the major pigment in plants, algae, and cyanobacteria?
chlorophyll
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What is the major pigment in green and purple bacteria?
bacteriocholorphyll
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Oxygenic means what?
use or produce oxygen
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Plants, algae, and cyanobacteria are oxygenic or anoxygenic?
oxygenic
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Green and purple bacteria are oxygenic or anoxygenic?
anoxygenic - they break down other compounds for electrons like H2S (hydrogen sulfide)- which produces sulfur
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What does the Calvin Cycle fix?
carbon dioxide
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How can organisms be divided when it comes to their metabolism?
by their primary source of energy and their primary source of carbon
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What are the choices of energy for organisms?
light (phototrophs), or chemicals absorbed from the environment (chemotrophs)
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Where can the sources of an organisms carbon be found?
carbon dioxide (autotrophs "self feeders") or organic molecules in the environment (heterotrophs "other eaters... carbohydrates, lipids)
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photoautotrophs are...? what do these include?
photosynthetic and fix CO2 for carbon -- classic photosynthetic organisms like plants, algae, and cyanobacteria
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Photoheterotrophs are...? these include?
photosynthetic, but they don't fix carbon (run light reactions, but not calvin cycle) they consume organic compounds (like fats) as carbon sources -- green and purple bacteria
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chemoautotrophs do what?
they fix carbon dioxide for their carbon, but do not have light reactions, they oxidize inorganic compounds (iron or sulfur) to release energy
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Where are chemoautotrophs capable of living and why?
Nutritionally extreme environments like volcanic deep sea vents or walls of caves -- they get their nutrients from the air
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Chemoautotrophs are also called what?
"rock eaters"
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Chemoheterotrophs include...? where do they get their energy?
all animals, algae, fungi, protozoa, and most bacteria --other organisms, they depend on the things produced by other organisms
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Chemoheterotrophs are called what? This includes mostly what?
"organic eaters" -- all pathogenic bacteria (food spoilage organisms)
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Chemoheterotrophs that get their organic molecules from living tissues are...? Those that get theirs from dead and decaying material are...?
parasites/saprophytes
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Bacteria and Fungi on Earth are what?
saprophytes
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How can bacteria be seperated into categories?
The temperature range each grow in. Since each grows in a different range, their growth can be controlled by altering temps (heating, cooling)
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What temp range do most microbes grow in? What does the optimum growth depend on?
30 degrees celsius -- the optimum temp for its enzymes
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Psychrophiles are known as? What is their optimum temperature range? Where are they found usually?
cold lovers -- 10 degrees celsius -- cold or icy places like ocean depths
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Where do psychrophiles grow?
Regrigeration/Freezer -- but don't really cause food spoilage or disease because they don't live in environments that humans live near
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Psychrotrophs are known as what? Grow best at what temperature range? Are usually what?
"cold eaters" -- 20 degrees celsius -- environmental bacteria
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These are usually responsible for what? What is an example? They are rarely what?
Food spoilage -- Psuedomonas fragi -- human pathogens, bc they dont grow at human body temperature
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Mesophiles are known as what? Grow at what optimum temp range? Nearly all of these are what?
"middle lovers" -- 37 degrees celsius -- human pathogens
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How can the growth of mesophiles be stopped? What is an example of a mesophile?
Cooling or refrigerating food -- Listeria monocytogenes (causes listeria)
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Thermophiles are known as what? Grow at what optimum temp range? and are usually found where?
"hot lovers" -- 60 degrees celsius -- hot springs or warm soils
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Thermophiles don't do what?
Cause disease or spoil food -- they can't grow at human body temp or at room temp/cooling temp
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Hyperthermophiles are known as what? Grow at what optimum temp? Are found where? They don't do what?
"very hot lovers" -- 90 degrees celsius -- boiling hot springs -- spoil foods or cause disease
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What is the "danger zone" for food? What is most likely to happen if food is in this zone? How can it be prevented?
60-130 degrees farenheit/15-50 degrees celsius -- growth of foodborne pathogens -- keep foods really hot or really cold for storage
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State law often requires restaurants to keep the temp for foods at what?
135 degrees farenheit
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Listeria monocytogenes can grow at what extreme temps? Clostridium perfringens?
<40 deg. faren -- >140 deg. faren.
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What bacteria is most commonly associated with soups and gravies?
clostridium perfringens -- endospores survive boiling and germinate when food is cooled down
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Since microbes require water to metabolize.. microbial growth can be controlled by...?
decreasing water content of foods
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foods with <20% of water...?
don't have microbial growth (crackers, raisins)
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what type of organism tolerates reduced water content (20-80%)? like what?
xerophiles -- bread & cheese
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What are most xerophiles?
molds
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How can microbial growth be controlled with pH?
acidifying foods
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What is the optimum pH of most bacteria? Marine bacteria?
6.5-7.5 -- 8.5 (pH of the ocean)
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What is the optimum pH of fungi?
5-6
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What are acidophiles called?
"acid lovers"
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Where do acidophiles grow? example?
in acidic environment of pH 4 of less -- Lactobacillus
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Lactobacillus is produced by what?
acidophiles
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What are the two strategies acidophiles use to resist the effects of acids?
Numerous hydrogen ion pumps to continuously eject H+ and maintain roughly neutral inner pH -- cytoplasm is acidic and all cells enzymes have acidic optima
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Depending on osmotic range, how can microbial growth be controlled?
by altering salt/sugar concentrations in foods
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Most bacteria we encounter tolerate what level of salt? marine bacteria?
less than 2%/ 3.5% (ocean salt level)
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What do high salt or sugar concentrations cause? What is the concentration in/out of cell normally?
plasmolysis (cell shrinkage due to loss of water) -- solute is greater inside cell
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How does plasmolysis happen?
when concentration of sugar or salts is high enough, osmotic movement of water reverses and water leaves cell
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What foods are protected by osmostic pressure?
honey, syrups, jelly, salted meats
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What are halophiles called? What do they tolerate?
"salt lovers" -- high salt concentrations
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Where are halophiles found in nature? Like where?
bodies of water with high salt concentrations -- great salt lake, dead sea, evaporation pond
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What pathogen has the highest salt tolerence? How much can it tolerate?
Staphylococcus aureus (causes staph infections) -- above 7% salt
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Obligate aerobes require what? Example?
oxygen - molds
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What three groups can anaerobes be divided into? examples?
- Facultative - don't require oxygen but can use it ( yeasts )
- aerotolerant - cannot use oxygen but tolerate its presence ( lactobacillus )
- obligate anaerobes - cannot use oxygen and are harmed by it (clostridium)
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Most bacteria fall under what with oxygen functions?
facultative anaerobes
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Oxygen is not usually toxic to cells, but what related compounds produced by oxygen are?
superoxide (O2-) - hydrogen peroxide (h2o2)
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How are superoxide and hydrogen peroxide produced? Why are they toxic?
mistaken during metabolism - they are reactive molecules
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The damage that ROS cause and pressure put on cells to survive is called what?
oxidative stress
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How can microbe tolerate the presence of oxygen?
they have enzymes to eliminate superoxide and peroxide
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Most bacteria multiply how? Others use what? Example of the second?
binary fission - spores - streptomyces
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What happens during binary fission?
single bacterium divides into two cells (there's no nuclues or spindle fibers)
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The time it akes to divide into two cells
generation time - doubling time
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The generation time of E. Coli in ideal conditions is what?
20 minutes - most bacteria are longer
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How are bacteria numbers given?
in exponential notation due to reproducing large numbers so quickly
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Growth of cell population refers to what?
cell population, not size
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When bacteria is introduced to a new environment it goes thruogh what four stages to growth-death?
lag, log, stationary, death
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Lag phase
adjustment time, cells are active but producing deifferent enzymes to fit its new environment - there's no growth
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log phase
a time of growth - metabolic machinery is dedicated to growth rather than defense so population is growing, but reproduction isn't high - vulnerabe to death by antibiotics
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stationary phase
a time of survival - growth stops because conditions are crowded and nutrients are low, so they stop to survive -- strongest against antibiotics
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death phase
time of death, nutrients has run out
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The ability to detect when conditions become crowded is called what?
quorom sensing
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