Koofers

exam 2 - Flashcards

Flashcard Deck Information

Class:BIO 014 - Principles of Microbiology
Subject:Biological Sciences
University:Solano Community College
Term:Spring 2013
- of -
INCORRECT CORRECT
- INCORRECT     - CORRECT     - SKIPPED
Shuffle Remaining Cards Show Definitions First Take Quiz (NEW)
Hide Keyboard shortcuts
Next card
Previous card
Mark correct
Mark incorrect
Flip card
Start Over
Shuffle
      Mode:   CARDS LIST       ? pages   PRINT EXIT
Microbial growth is the increase in...
in number of cells,
not cell size
Why is it important to understand the conditions necessary for microbial growth? We want to encourage the good ones( fermentation, beer ,wine) and prevent pathogenic pathogens from growing (food spoilage)
Obtaining Carbon
Heterotroph are?
an organism that must
obtain carbon in an organic form made by
other living organisms: proteins,
carbohydrates, lipids and nucleic acids
Generated by Koofers.com
Autotroph are?
organism that uses CO2, an
inorganic gas, as its carbon source
Nutrients:
Inorganic nutrients are?
atom or molecule that contains a
combination of atoms other than carbon and hydrogen:
 metals and their salts (magnesium sulfate, ferric
nitrate, sodium phosphate), gases (oxygen, carbon
dioxide) and water
Organic nutrients are?
contain carbon and hydrogen atoms
and are usually the products of living things:
 methane (CH4), carbohydrates, lipids, proteins, and
nucleic acids
Generated by Koofers.com
Energy Sources
Phototroph are?
use light as their primary
energy source
Chemotroph are?
depend on 0xidationreduction
reacitons of inorganic or organic
compounds for energy
Metabolic Diversity Among Organisms (CH 5) (Pages 142-145)
Macronutrients – required in large quantities; play principal roles in cell structure & metabolism Fig 5.28
 proteins, carbohydrates
 Micronutrients or trace elements – required in small amounts; involved in enzyme function & maintenance of protein
structure manganese, zinc, nickel
Generated by Koofers.com
Physical Requirements for Growth
Temperature
 pH
 Osmotic Pressure
What are the three types ofTemperature?
 Minimum growth temperature
 Optimum growth temperature
 Maximum growth temperature
How does high temperature (above normal) affect MO growth?
Bacteria cannot control their internal temperature so it will be the same as their
surroundings. At very low temperatures the PM will lose fluidity and transport across
it will cease; at high temperatures proteins and nucleic acids will denature.
Psychrophiles (G = cold loving)
Obligate Psychrophiles
 Topt ~15°C; cannot grow above 20°C
 Common in the Arctic, Antarctic, Mountains, and
Ocean Floor
 Rarely involved in food preservation problems
Generated by Koofers.com
Psychrophiles (G = cold loving)
Facultative Psychrophiles
 Topt ~15°C; but can grow at higher temperatures
What do the terms OBLIGATE and FACULTATIVE MEAN? Obligate means the organism have to have it.
Faculatative means means "optional" or "discretionary" 
Facultative anaerobe, an organism that can use oxygen but also has anaerobic methods of energy production. It can survive in either environment
Mesophiles (G = middle loving)
Optimum 25° to 40°C
 Most microbes, most human pathogens, most culture incubators
37ºC
 Psychrotrophs (G. feeder)
 Term used by food microbiologists
 Grow best at or above 20°C but can grow at low
temperatures
 Often responsible for spoilage of refrigerated food (4ºC)
 Mold mycelium, slime on food surfaces, or off-tastes and
off colors in foods.
Thermophiles (G = heat loving) Facultative Thermophiles
Facultative Thermophiles
 Grow best above 45° but can grow at lower temperatures
 Common in Compost Heaps, surface soil, and “cooler” Hot
Springs
Generated by Koofers.com
Thermophiles (G = heat loving) Obligate Thermophiles
Obligate Thermophiles
 Cannot grow below 45°
 Optimum 50° to 60°
 Common in Hot Water Lines, Hot Springs
Hyperthermophiles (Archae)
Optimum > 80°C
 Sulfuric hot springs, Hydrothermal deep ocean vents
[box p.164-5]
 Strain 121 (Pyrococcus furiosus) is a recently
discovered Archae
 Polymerase chain reaction (PCR)
 grows in the autoclave 121C, survived 130C
for 2 hrs.Fuel production,Industrial applications
LOOKING AHEAD: The Enzyme Taq Polymerase, produced by the Obligate Thermophile  Industrial applications Thermus aquaticus, is vital to the Polymerase Chain Reaction (PCR) (Chapter 9).
Physical Requirements for Growth
pH
 Most bacteria grow between pH 6.5 and 8.5
 Acidophiles can grow in acidic environments
 Fungi (molds and yeasts) grow between pH 5 and 6
 Acidic foods such as pickles, cheese, sauerkraut/kimchee have low
enough pH to discourage growth of bacteria and most fungi
 Many microbes produce acid as a product of metabolism so most
culture media contains buffers to minimize or delay the resulting drop
in pH
 Our stomach acid keeps us from getting sick from the majority
of bacteria, except a few. Which ones?
Generated by Koofers.com
Our stomach acid keeps us from getting sick from the majority of bacteria, except a few. Which ones? Heliobacter pylori, ecoli
Physical Requirements for Growth Osmotic pressure
Microorganisms obtain most of their nutrients in
solution from the surrounding water.
 Hypertonic environments, increase salt or sugar,
cause plasmolysis (cells shrink = lose water)
 Salted fish, honey, and sweetened condensed
milk = preserved foods
 Some organisms have adapted: Extreme or obligate
halophiles require high osmotic pressure
 Facultative halophiles tolerate high osmotic pressure
Our skin is normally high in salt concentration so most bacteria will not grow there. Some, though, e.g., Staphylococcus aureus actually like it!
Generated by Koofers.com

List View: Terms & Definitions

  Hide All 27 Print
 
Front
Back
 Microbial growth is the increase in...
in number of cells,
not cell size
 Why is it important to understand the conditions necessary for microbial growth?We want to encourage the good ones( fermentation, beer ,wine) and prevent pathogenic pathogens from growing (food spoilage)
 Obtaining Carbon
 Heterotroph are?
an organism that must
obtain carbon in an organic form made by
other living organisms: proteins,
carbohydrates, lipids and nucleic acids
 Autotroph are?
organism that uses CO2, an
inorganic gas, as its carbon source
 Nutrients:
 Inorganic nutrients are?
atom or molecule that contains a
combination of atoms other than carbon and hydrogen:
 metals and their salts (magnesium sulfate, ferric
nitrate, sodium phosphate), gases (oxygen, carbon
dioxide) and water
 Organic nutrients are?
contain carbon and hydrogen atoms
and are usually the products of living things:
 methane (CH4), carbohydrates, lipids, proteins, and
nucleic acids
 Energy Sources 
 Phototroph are?
use light as their primary
energy source
 Chemotroph are?
depend on 0xidationreduction
reacitons of inorganic or organic
compounds for energy
 Metabolic Diversity Among Organisms (CH 5) (Pages 142-145)
Macronutrients – required in large quantities; play principal roles in cell structure & metabolism Fig 5.28
 proteins, carbohydrates
 Micronutrients or trace elements – required in small amounts; involved in enzyme function & maintenance of protein
structure manganese, zinc, nickel
 Physical Requirements for Growth
Temperature
 pH
 Osmotic Pressure
 What are the three types ofTemperature?
 Minimum growth temperature
 Optimum growth temperature
 Maximum growth temperature
 How does high temperature (above normal) affect MO growth?
Bacteria cannot control their internal temperature so it will be the same as their
surroundings. At very low temperatures the PM will lose fluidity and transport across
it will cease; at high temperatures proteins and nucleic acids will denature.
 Psychrophiles (G = cold loving)
Obligate Psychrophiles
 Topt ~15°C; cannot grow above 20°C
 Common in the Arctic, Antarctic, Mountains, and
Ocean Floor
 Rarely involved in food preservation problems
 Psychrophiles (G = cold loving)
Facultative Psychrophiles
 Topt ~15°C; but can grow at higher temperatures
 What do the terms OBLIGATE and FACULTATIVE MEAN?Obligate means the organism have to have it.
Faculatative means means "optional" or "discretionary" 
Facultative anaerobe, an organism that can use oxygen but also has anaerobic methods of energy production. It can survive in either environment
 Mesophiles (G = middle loving)
Optimum 25° to 40°C
 Most microbes, most human pathogens, most culture incubators
37ºC
 Psychrotrophs (G. feeder)
 Term used by food microbiologists
 Grow best at or above 20°C but can grow at low
temperatures
 Often responsible for spoilage of refrigerated food (4ºC)
 Mold mycelium, slime on food surfaces, or off-tastes and
off colors in foods.
 Thermophiles (G = heat loving) Facultative Thermophiles
Facultative Thermophiles
 Grow best above 45° but can grow at lower temperatures
 Common in Compost Heaps, surface soil, and “cooler” Hot
Springs
 Thermophiles (G = heat loving) Obligate Thermophiles
Obligate Thermophiles
 Cannot grow below 45°
 Optimum 50° to 60°
 Common in Hot Water Lines, Hot Springs
 Hyperthermophiles (Archae)
Optimum > 80°C
 Sulfuric hot springs, Hydrothermal deep ocean vents
[box p.164-5]
 Strain 121 (Pyrococcus furiosus) is a recently
discovered Archae
 Polymerase chain reaction (PCR)
 grows in the autoclave 121C, survived 130C
for 2 hrs.Fuel production,Industrial applications
 LOOKING AHEAD: The Enzyme Taq Polymerase, produced by the Obligate Thermophile  Industrial applications Thermus aquaticus, is vital to the Polymerase Chain Reaction (PCR) (Chapter 9). 
 Physical Requirements for Growth
pH
 Most bacteria grow between pH 6.5 and 8.5
 Acidophiles can grow in acidic environments
 Fungi (molds and yeasts) grow between pH 5 and 6
 Acidic foods such as pickles, cheese, sauerkraut/kimchee have low
enough pH to discourage growth of bacteria and most fungi
 Many microbes produce acid as a product of metabolism so most
culture media contains buffers to minimize or delay the resulting drop
in pH
 Our stomach acid keeps us from getting sick from the majority
of bacteria, except a few. Which ones?
 Our stomach acid keeps us from getting sick from the majority of bacteria, except a few. Which ones?Heliobacter pylori, ecoli
 Physical Requirements for Growth Osmotic pressure
Microorganisms obtain most of their nutrients in
solution from the surrounding water.
 Hypertonic environments, increase salt or sugar,
cause plasmolysis (cells shrink = lose water)
 Salted fish, honey, and sweetened condensed
milk = preserved foods
 Some organisms have adapted: Extreme or obligate
halophiles require high osmotic pressure
 Facultative halophiles tolerate high osmotic pressure
 Our skin is normally high in salt concentration so most bacteria will not grow there. Some, though, e.g., Staphylococcus aureus actually like it! 
36, "/var/app/current/tmp/"