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Final Exam
Food micro, environmental micro
169
Microbiology
Undergraduate 2
04/29/2014

Additional Microbiology Flashcards

 


 

Cards

Term
How many different serotypes or species of salmonella are there?
Definition
30
Term
Food spoilage can come from many microbial sources. What are some of them?
Definition

Moldy bread - fungi

Contaminated meat - bacteria

Shellfish - live in brackish water which has many toxins

 

Term
What was the strain of salmonella that is associated with a breakout in a correctional facility that was traced back to Tyson's chicken? Why was this strain such a problem?
Definition

Heidelburg; pan resistant 75%

 

Term
How long does it take the CDC/FDA to gain enough info to identify a strain associated with an outbreak/make a recall on food?
Definition
1-2 weeks
Term
How does the CDC/FDA identify the species of salmonella? What area of micro is associated with this?
Definition
Identifications made by analysis of DNA. Molecular biology
Term
Who is most at risk for death from food poisoning?
Definition
Young children and the elderly. Not a large killer of healthy individuals.
Term
Factors influencing microbial growth
Definition

Water content

pH

Physical structure

Chemical composition

O2 availability

Temperature

Term

Describe the requirement for microbial growth:

 

Water content

Definition
Microbes need water. Very dry foods have less microbes
Term

Describe the requirement for microbial growth:

 
pH
Definition
Neutral is more preferable
Term

Describe the requirement for microbial growth:

 
Physical structure
Definition

Ground beef has more microbes than steak.

If a fruit or vegetable has a peel, it protects it better against microbes

How food is stored is also important

Term

Describe the requirement for microbial growth:

 
Chemical composition
Definition
Foods that are more acidic will have less microbial growth.
Term

Describe the requirement for microbial growth:

 
O2 availability
Definition
Microbes need lots of O2
Term

Describe the requirement for microbial growth:

 
Temperature
Definition
Mesophilic
Term
What do molds breakdown?
Definition
Carbohydrates
Term
Molds like a high ______ content
Definition
sugar
Term

The following foods are perishable/nonperishable:

 

fish, poultry, eggs

Definition
Perishable; spoil quickly
Term

The following foods are perishable/nonperishable:

 
dry spaghetti, dry beans, coffee, raisins
Definition
nonperishable; last a long time without going bad
Term
The consumption of _____ or ______ can cause food poisoning and infections
Definition
toxins or microorganisms
Term

Intrinsic or extrinsic?

 

Antimicrobial substances, some herbs tend to carry foodborne bacteria, polyphenol

Definition
Intrinsic
Term
Intrinsic or extrinsic?
Definition
temperature, humidity, contaminating organisms
Term
A toxin produced by aspergillus flavus that is cancer causing in vertebrates; linked to liver and colon cancers
Definition
Aflatoxin
Term
What produces aflatoxins?
Definition
Aspergillus flavus
Term
What is aflatoxin accumulated in?
Definition
Grains, nuts, corn
Term
A condition inducing convulsions and hallucinations from fungal toxins in rye
Definition
Ergotism
Term
What causes ergotism? And what famous historical event is it associated with?
Definition
Claviceps purpurea; Salem witch trials
Term
Claviceps purpurea which causes ergotism, is found in what?
Definition
Rye, wheat, barley
Term
What are some physical methods of controlling microbial growth in food?
Definition
Filtering, refrigeration, freezing, heat
Term
This is used in deli meats. High volume of CO2 (60%) reduces the oxygen content in bacterial, therefore reducing gram negative bacteria on meat.
Definition
Modified atmosphere packaging
Term
How does heating affect microbes?
Definition
Heat kills microbes
Term
How does refrigeration affect microbes?
Definition
Refrigeration slows the growth of microbes
Term

What are the following known as?

 

Propionic acid

Sorbic acids

Benzoic acids

Sulfites

Sodium diacetate

Sodium nitrite

 

Definition
Preservatives
Term

Identify the preservative:

 

Prevents molds on bakery goods

 

inhibits enzymes by lowering pH

 

Preservative for both animal feed and food for human consumption

Definition
Propionic Acid
Term
Inhibits enzymes by lowering pH
Definition
Identify the MOA of propionic acid
Term

Identify the preservative:

 

Natural organic compound

All salts are associated with this preservative

Prevents molds in cheeses, syrups, cakes

Prevents growth of mold/yeast/fungi in food and drinks (pop and juices)

Definition
Sorbic acid
Term

Identify the preservative:

 
prevents molds in margarine and low pH products
Definition
Benzoic acids
Term

Identify the preservative:

 
Wines, lemon juices (NO meats)
Dried fruits
inhibits enzyme that causes "browning"
Can potentially make allergies worse
Antibacterial and antifungal SO2
Definition
Sulfites
Term
What is the enzyme that causes "browning"?
Definition
Phenolase
Term

 

Inhibit enzyme that causes "browning"

Definition

 MOA of sulfites

 
Term

Identify the preservative:

 
Prevents molds on breads
Definition
Sodium diacetate
Term

Identify the preservative:

 
Prevents botulism (clostridum)
Inhibit iron-sulfur clusters
Inhibits lipid oxidation
Found in chicken and hotdogs
Can form nitrosamine-this can be inhibited by vitamin C
Do not consume when pregnant
Definition
Sodium nitrite
Term
Inhibition of iron sulfur clusters which are essential to energey metabolism of Clostridium botulinum. Inhibits gram neg bacteria
Definition
Sodium nitrite
Term
What is our concern with the use of sodium nitrite as a preservative?
Definition
Nitrosamine formation; this occurs when the preservative is cooked and it combines with amino acids to produce nitrosamine which is a known carcinogen :(
Term
What can help prevent nitrosamine formation?
Definition
Vitamin C; asorbic acid
Term

Identify the preservative:

 
Phenolase inhibitor
Found with vitamin C as an antioxidant
Derivatives prevent fat oxidation
Definition
Citric acid and asorbic acid
Term
One of a group of bacterial proteins toxic to other bacterial cells. Produced by bacteria to kill bacteria (attach to plasma membrane and lyse cell)
Definition
Bacteriocins
Term

Identify the preservative:

 
Produced from lactococcus lactis
Contains bacteriocins which are an antibioitic compound that kills bacteria
Found in lloyds pulled pork
Definition
Nisin
Term
Contains bacteriocins which attach to plasma membrane of bacteria and lyse cell
Definition
Nisin
Term

Identify the food-borne disease:

 

Bacterial pathogen found in deli meats that causes food poisoning. Found mainly in prepackaged deli meats. Considering use of bacteriophage spray to reduce instances.

Definition
Listeria
Term

Identify the food-borne disease:

 

Norwalk virus. Named after Norwalk Ohio. Get it from food, direct/indirect contact. Found in shellfish and salad.

Definition
Norovirus
Term

Identify the food-borne disease:

 

Found in ground beef that is undercooked

Definition
E.Coli 0157:H7
Term

Identify the food-borne disease:

 

Toxin producer found in eggs

Definition
Shigella
Term

Identify the food-borne disease:

 

Found in shellfish, causes GI disease

Definition
Vibrio parahaemolyticus
Term

All the following foods are an example of what?

 

Milk products, meat/fish, alcohol, breads, tofu, tempeh, pickles/kraut, soy sauce, kimchi

Definition
Foods fermented by microbes
Term
Bacteria involved in making cheese. Also found in buttermilk, sour cream, and keifer
Definition
lactobacillus, lactococcus lactis
Term
Where does milk pick up bacteria?
Definition
Sterile in cow's udder, picks up bacteria in the milking process
Term
This is what you innoculate foods with. Isolated bacteria. Many people retain small amounts of previously made yogurt, cheese, etc.
Definition
Culture/starter
Term
How do lactobacillus and lactococcus lactis work?
Definition
They ferment lactic acid from lactose
Term
How do cultures/starters affect food?
Definition
Lower pH
Term
What is the liquid part of cottage cheese/yogurt called?
Definition
Whey
Term
When milk curdles to form cheese or cottage cheese, what is produced and what is formed?
Definition
Acid is produced and caseinase is formed
Term
What is the sugar found in milk
Definition
lactose
Term
What is the #1 species for making cheese?
Definition
Lactococcus lactis
Term
Mongolian. Kept in leather bag which is easy to keep fermented. Can have some alcoholic content
Definition
Kefir
Term
What must you first do with milk or sour cream before innoculating it?
Definition
Boil to kill bad bacteria
Term
Contains more protein and less whey. More compacted. Also contains a different strain of lactococcus
Definition
Greek yogurt
Term

Contains streptococcus thermophilius and lactobacillus bulgariucs; like around 75-80 degrees celsius.

 

Created through a thermophilic process

 

Definition
Yogurt
Term
Where do microbes originate in foods like sausage, salami and pepperoni?
Definition
Microbes comes from casings and environments in which the food is made
Term
_______ foods are more easily preserved, known to have a high number of vitamins, easily digestable, antioxidants, probiotics
Definition
Fermented foods
Term
Yeast does fermenting. Do not want bacteria involved or present. Produces carbon dioxide gas during process
Definition
Production of Ethanol/Alcohol
Term
What is important when fermenting alcohol?
Definition

No bacterial contamination

No air otherwise the yeast will produce ethanoic acid which is the chemical in vineagar

Term
If air is allowed in fermentation of alcohol, what will be produced?
Definition
Ethanoic acid - chemical found in vinegar
Term
What is the beer starter known as?
Definition
wort
Term
What is involved in the making of bread?
Definition
Fermentation; yeast is mixed with dough and kept warm. Carbon dioxide makes the bread dough rise and alcohol evaporates
Term
Set of freeze dried bacteria that will activate when they reach the colon
Definition
Probiotics
Term

Must not be pathogenic or carrying resistance genes

Must be able to get past acidic environment of the stomach

Very strict regulations

Definition
Probiotics
Term
These are given preemptively to cattle, chickens to prevent campylobacter and salmonella.
Definition
Probiotics
Term
What kind of microbes do the work of composting?
Definition
Aerobic microbes
Term
How long must composte be treated in order to be usable at OU?
Definition

14 days inside composting machine

90 days outside 

Term
What must be present inside the in vessel composter at OU for composting to happen?
Definition
Needs air. Has a lot of fans to keep O2 going so that microbes and other organisms are kept alive
Term
What goes into the composter here at OU?
Definition

Paper

Food waste

Service ware PLA

Bulking agent (mulch, etc.)

Term
Process by which organic substances are broken down into smaller compounds by living microbial organisms
Definition
Biodegradation
Term
What is the gas produced from landfill waste?
Definition
Methane
Term
What gives earthy smell to compost?
Definition
Actinomycetes
Term
What microbes do the work of composting?
Definition

Mesophiles: lactobacillus spp acetobacter

As it heats up, thermophiles take over: bacillus spp and actinobacteria

Term
What should end product of compost not contain?
Definition
Pathogens or viable seeds
Term
EPA waste diversion mandates that federal agencies must reduce waste by ____ by fiscal year 2015.
Definition

50%

 

States mandate states

Term
How many tons of food are produced each day at OU?
Definition
6 tons daily
Term
A corn/starch based bioplastic that can be broken down in a landfill in 14 days compared to the 1,000 years of other plastics that arent treated
Definition
Plastarch material
Term
Organic substances are broken down into smaller compounds by living microbial organisms
Definition
Biodegredation
Term
Bacteria ferments sugar by bacteria and turns it into lactic acid. Lactic acid beads are then formed into products. This is biodegradable. Cannot be heated!
Definition
PLA plastic
Term
Why do we need biodegradable plastic?
Definition
2 large patches in each ocean of garbage approx size of pennsylvania. These flow and vortex in oceans. Contain hundreds of microbes that help break down plastic-many vibrio species
Term
Water borne pathogens; fecal contamination
Definition
Coliforms
Term
Indicator species of fecal contamination; most common?
Definition
E.Coli
Term
What is the 3 step process of water purification? (drinking water)
Definition

Sedimentation

Filtration

Chlorination

Term

Identify the process of drinking water treatment:

 

Removes large objects and particles through flocculation

Definition
Sedimentation
Term

Identify the process of drinking water treatment:

 

Removes microorganisms by passing water through a layer of sand, gravel, microbe biofilm, carbon

Definition
Filtration
Term

Identify the process of drinking water treatment:

 

Involves addition of chlorine gas to kill remaning organisms

Definition
Chlorination
Term
What are the two techniques used to determine numbers of bacteria in a water sample?
Definition
Membrane filter technique, standard plate count (SPC)
Term
Test determines number of bacteria by observing carbon dioxide gas production
Definition
Most probably number (MPN)
Term
Who regulates water quality?
Definition
EPA
Term
What is acceptable level of coliforms for drinking water?
Definition
Less than 1 coliform per 100 ml's
Term
If coliforms are found in more than ___% of drinking water, quality isnt accepted
Definition
5%
Term
What are the three steps in sewage treatment?
Definition
Screen, sediment, sludge. Ends with chlorination
Term
What happens once waste water is turned to sludge?
Definition
Done aerobically and anaerobically; can be turned into fertilizer or dried and buried
Term
What are the 3 biochemical cycles?
Definition

Carbon

Nitrogen

Sulfur

Term
What do soil microorganisms do?
Definition
Break down organic molecules from dead and dying things
Term
These organisms convert Co2 into carbohydretes - carbon fixation
Definition
Photosynthetic organisms
Term
What retains most of the carbon in our atmosphere?
Definition
Oceans
Term
Convert dead organic matter to release CO2 for reuse by plants
Definition
decomposers
Term
What must atmospheric carbon be kept at to keep global warming at halt?
Definition
350 ppm's
Term
What is climate change caused by?
Definition
Carbon levels
Term
How much carbon you used in your lifetime
Definition
Carbon footprint
Term
Atmospheric carbon contributes to what?
Definition

Greenhouse effect

acid rain

Term

Causes breakdown of coral reefs

pH of oceans will affect this a lot

Acid rain on mountain tops; ruins soil and causes trees to dry out and die

Definition
Acidification
Term
What is a source of local acidification?
Definition
Acid mine drainage. Water that comes through them becomes polluted and pollutes water sources. This kills fish, microinvertabrates, causes dead patches in streams
Term
What must both drinking water and sewage water undergo before going back into the system?
Definition
Chlorination
Term
Excess nitrates (NO2) and sulfates (SO2) cause pollution. What type of pollution is this?
Definition
Sulfur pollution
Term
Excess nutrients are feeding microbes and large algal blooms are created. WHen they die cause excess organic material to collect on the bottom
Definition
Dead zones
Term
Level of O2 in water that will sustain life
Definition
BOD
Term
Make low pH water neutral pH once it gets through system. Microorganisms in the shallow water and muck use anaerobic metabolism use alternate electron acceptors such as nitrate/sulfate
Definition
Buffer zones
Term

Uses a muck sample to analyze for microorganisms

Compares sulfur oxidation, photosynthesis, etc

Put in muck, sulfur sample, and pond water

Anaerobes at bottom photosynthesizers at top

2-3 months incubation

Definition
Winogradiski Column
Term
Helps to clean up pollution naturally using microbes. Reduce PCB's and TCE (Known carcinogens)
Definition
Bioremediation
Term
Have to be careful that microbes released wont affect other organisms. These unintended effects are known as what?
Definition
Non-target effects
Term
What species are pivotal in the cleaning up of oil spills?
Definition
Pseudomonas
Term
During this process, organic compounds are converted to inorganic compounds
Definition
Mineralization
Term
Microbes release what substance?
Definition
Nitrogen
Term
Beginning of nitrogen cycle. Breakdown of dead and decaying material into ________.
Definition
Ammonification; ammonia
Term
What is broken down into ammonia during ammonification?
Definition
Urea
Term
Second step of nitrogen cycle following ammonification. It is a 2 step process. Converts ammonia to nitrite and then nitrite to nitrate
Definition
Nitrification
Term
During the first step of nitrification; what happens? And what species carry it out?
Definition

Ammonia to nitrite.

Nitrosococcus

Nitrosomonas

Term
During the second step of nitrification; what happens? What species are responsible?
Definition

Nitrite to nitrate

 

Nitrococcus

Nitrobacter

Term

Third step of nitrogen cycle following nitrification.

 

Involves taking nitrate to nitrogen gas. This replenishes the atmosphere

Definition
Denitrification
Term
What species carries out denitrification?
Definition
Pseudomonas
Term
What is the bad greenhouse gas that can be given off by denitrification?
Definition
Nitris oxide
Term
Taking nitrogen gas and converting it to organic nitrogen.
Definition
Nitrogen fixation
Term
What species carries out nitrogen fixation?
Definition
Rhizobium (bacteria) Legumes, clover have pockets called nodules (located in roots) that contain this.
Term
Fungal symbiotic relationships with plant roots. Make plants more efficient in absorbing nutrients
Definition
Mycorrhizae
Term
Plant pathogen (bacteria) that causes tumor to form by horizontal gene transfer. The bacteria affects DNA in plants (bacterial DNA found in nucleoid region) creates pili between bacteria and plant cell. Will express virulent DNA which produces massive growth in tissue.
Definition
Agrobacterium
Term
What does virulent DNA that causes tumor growth in plants produce that is helpful to harmful bacteria?
Definition
Opines
Term
Scientific model for GMO's Do experiments on this much like we test meds on mice
Definition
Arabidopsis Thalliana
Term
What is the photosynthetic part that plants possess?
Definition
Chloroplasts
Term
What was the first photosynthesis carried out by?
Definition
Cyanobacteria
Term
How many phases does photosynthesis have? And what are they?
Definition
2 phases; light and dark
Term
In this phase of photosynthesis; plant absorbs energy from the sun. Shifts around electrons through an ETC. NADPH and ATP created travel to calvin cycle. CO2 fixed into larger carbohydrate and releases O2
Definition
Light cycle
Term
What is created in the light phase of photosynthesis?
Definition
NADPH and ATP
Term
In this phase of photosynthesis, CO2 is incorportaed into sugar. Energy from other phase drives this
Definition
Dark phase
Term
One celled euk. photosynthesizers
Definition
Algae
Term
What do photosynthetic bacteria have?
Definition
Thylakoids
Term
This is found with cyanobacteria in marine ecosystems
Definition
microalgae
Term
Zoo plankton. Symbiotic relationships between larger animals that provide nutrients heterotrophic or photosyntheic
Definition
Zooxanthaellae
Term
Biological phenomenon that indicates growth in response to an environmental stimulus
Definition
Tropism
Term
Tiny organism that lives within dinoflagellates
Definition
Roseobacter clade
Term
What does the sulfur smell of the ocean come from? Other ocean smell?
Definition
Dinoflagellates. DMSP
Term
In earthworm group. Live near hydrothermal vents where no sunlight is present. Surround water is very cold but vents are very warm
Definition
Hydrothermal vent tube worms
Term
Have no digestive system. Have a symbiotic relationship with bacteria that live in trophosomes and feed them. Discovered by Colleen Cavanaugh
Definition
HTV Tube worms
Term
Only eat wood (carbon/cellulose) have many bacteria/archea/protists that help it digest it and allow them to use it as a nutrient source. Contain nitrogen fixing bacteria that converts nitrogen gas to organic nitrogen
Definition
Termites
Term
Complex parasitic euk. that wouldnt be symbiotic without bacteria.
Definition
Nematodes
Term
C. elegans is what?
Definition
Eukaryotic cell model; behave similarily to human cells
Term
When using bio control, we want to consider these because their effects are often much more damaging than predator-prey interactions
Definition
Nematodes
Term
HB bacteria interacts with these. Live inside them and fluoresce. Virulent bacteria that kills caterpillars in 24-48 hours.
Definition
Nematodes
Term
An association between a fungal mycelium and a cyanobacterium or alga
Definition
Lichens
Term
Lichens are composed of what 2 organisms?
Definition
Fungi and cyanobacteria
Term
Where do lichens grow? What do they replenish? What are they good indicators of?
Definition
Rock and stone. Break them down into soil. They replenish soil. Good indicators of pollution because they do not grow well in areas that are highly polluted.
Term
Microbes that glow are said to what?
Definition
Bioluminesce
Term
Sea water vibrio that helps squid to glow because of the light this bacteria gives off. Helps the squid to appear to be a part of the night sky when the predators look up at it. Camo!
Definition
Vibrio Fischeri
Term
"Cud chewers" cows, sheep, deer. 4 chambers to stomach. Regurgitate food and chew again
Definition
Ruminants
Term
If the diets of ruminants are changed suddenly, what can affect them that is potentially fatal?
Definition
Acidosis
Term
In humans these form a symbiotic relationship
Definition
Gut microbiota
Term
An interrelationship between 2 populations of organisms where there is a close and permanant association
Definition
Symbiosis
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