Micro Lab Last Test

Front 1

1. what is the mechanism of dry heat?
2. what is the use of heat?
3. what is the purpose of moist heat?
4. what is the problem of moist heat?
5. what is the mechanism of moist heat?

Back 1

1. coagulation of proteins; accumulation of free radicals (DNA damage)
2. sterilization of glassware, etc…. (things that tolerate high heat without damage
3. Production of water vapor results in much better transfer than dry heat
4. Boiling does not kill spores
Pasteurization only kills certain pathogens
5. Enzyme denaturation
Protein coagulation

Front 2

1. what is the purpose of the autoclave?
2. what is TDT?
3. what is DRT?
4. what is TDP?
5. forms of ionizing raditation

Back 2

1. By increasing the pressure within a closed vessel, you can raise the boiling temperature of water; Kills endospores
2. thermal death time
Time required to kill a specific bacteria at a specific temperature
3. decimal reduction time
Time required to kill 90% of organisms present
4. thermal death point
Temperature required to kill all bacteria in a liquid culture in 10 minutes
5. X – rays and gamma rays

Front 3

1. Main problem with free radicals
2. when electromagnetic radiation that does not have sufficient energy to remove electrons from the outer shells of atoms is called
3. 200 – 290 nm range; Biocidal – most lethal of the group, Causes direct DNA damage; damages collagen fibers; destroys vitamin A
4. overexposure causes sunburn
5. 320 – 400 nm

Back 3

1. induction of DNA strand breaks
2. non-ionizing radiation
3. UVC
4. UVB
5. UVA

Front 4

1. what happens to DNA when it is damaged by UVB?
2. what is light repair?
3. what is dark repair?
4. what is Xeroderma pigmentosum (XP)
5.

Back 4

1. UV light causes adjacent thymines to pair – formation of a pyrimidine dimer; “bulge” in the double helix – must be repaired before replication; if not repaired mutations may result
2. Photolyases activated upon exposure to visible light to repair damage
3. repair activation is Not dependent upon the presence of light
4. Extreme sensitivity to UV light
because the person cant repair the UV damage (defective nucleotide excision repair pathways)

Front 5

1. Most frequently used in water quality assessment ; qualities?
2, 3 stages of coliform technique
3. what is used for the confirmed test?
4. why is MUG agar used?

Back 5

1. coliforms
Aerobic or facultatively anaerobic
Gram - rod shaped bacteria
opportunistic
2 Presumptive
Confirmed test
Determination of the # of coliforms
4. Samples from + presumptive test tube at highest dilution used for confirmed test
Usually done on MUG agar
5. Differential for production of B-glucuronidase enzyme (GUD)
GUD converts MUG to a fluorescent compound that is visible with a UV lamp

Front 6

1. how to detect coliforms
2. Technique used to detect fecal contamination of water is called the; what do you do?
3. Filtering is a technique also commonly used for

Back 6

1. lactose fermentation tubes 1:2:1 and look at the chart.. then you can plate it and look for e.coli (glows)
2. membrane filter technique; Water is drawn through a thin filter; Bacteria are trapped on the filter
Place filter onto a nutrient agar plate; incubate; observe bacterial growth If use EMB – select for E. coli – common coliform
4. sterilization of heat labile substances

Front 7

1. what does TNTC?
2. what does TFTC?
3. what is salmonella-shingella argar selective for? differental?
4. Majority of GI pathogens ____ lactose, while the majority of intestinal normal flora ____lactose

Back 7

1. too numerous to count
More than 250 colonies per plate
2. to few to count
Less than 25 colonies per plate
3. Bile salts and dyes (brilliant green) inhibit Gram + and most Gram negative bacillil Lactose/neutral red – if ferment, form red colonies; non-fermenters form colorless colonies
Sodium thiosulfate/Ferric citrate – colonies with black centers are + for H2S production
4. do not ferment, ferment

Front 8

1. PEA agar (phenylethyl alchohol agar)
selective
2. EMB?
3. Pseudomonas P agar
4. the ability of an individual to produce offspring.
5. a trait that increases the fitness of an individual in a particular environment.

Back 8

1. gram positive
2. selective for Gram negative bacilli; lactose fermenters
3. Psuedomonas spp.
4. fitness
5. adaptation

Front 9

1. 3 possible scenarios of UV mutagenesis
2. BASIC PROCEDURE – form of replica plating
3. principle?

Back 9

1. No damage to bacterial cell’s DNA
Induced formation of T-T dimers; damage repaired by DNA repair pathways
Induced formation of T-T dimers; not repaired; possible mutation results in gene containing T-T dimer
2. Master plate with isolated colonies on enriched medium exposed to UV light
Using sterile toothpick, pick an isolated colony from the master plate and “rub” (transfer) the isolated colony to:
A TSA plate
A glucose minimal media plate
3. If a T-T dimer occurred in a gene involved in transport or utilization of glucose and was unrepaired a mutation will result
Mutant colonies will grow on the TSA, but not on the glucose minimal media

Front 10

1. what is transformation?
2. what is a plasmid?
3. what is a vector?
4. what does Beta Lactamase do?
5. what does araC regulator protein do?
6. Green Fluorescent Protein is AKA

Back 10

1. Uptake of naked, foreign DNA, often a circular plasmid
2. A circular piece of autonomously replicating DNA
3. a DNA molecule used to insert foreign DNA into a host cell
4. amp resistance
5. Regulates GFP transcription
6. Aequorea victoria jellyfish gene

Front 11

1. how does the bla gene work?
2. what does the calcium chloride do?
3. what does the heat shock do?
4. what does the LB broth do?
5. what is the common cause of teenage acne?

Back 11

1. cleaves the β-lactam ring of ampicillin molecules, which leaves them unable to interfere with peptidoglycan synthesis
2. neutralize the repulsive negative charges of the phosphate backbone of the DNA and the phospholipids of the cell membrane, allowing the DNA to enter the cells
3. increases permeability of cell membrane
4. allows beta lactamase expression
5. propionbacteria (makes skin acidic 3-5pH)

Front 12

1. what is the Most common cause of staphylococcal infections of the skin
2. what causes furuncles and carbuncles?
3. what Causes layers of the skin to detach; followed by peeling away of the detached layers
4. MSA agar is selective for? differental?
5. S. aureus coagulase enzyme reacts with ____in the blood.

Back 12

1. s. aureus aka the golden cluster seed
2. caused by the inflammation of hair follicles, thus resulting in the localized accumulation of pus and dead tissue. Individual boils can cluster together and form an interconnected network of boils called carbuncles.
3. Staphylococcal Scalded Skin Syndrome; Desquamative rash;
4. Selects for G + organisms such as staphylococcus spp.
Why? Many G+, esp. Staph spp. are halophilic, while many G- organisms such as E. coli are not; Presence of mannitol
Both S. aureus and S. epidermidis will grow on MSA, but only S. aureus will ferment mannitol
Yellow color change results from + fermentation
5. prothrombin

Front 13

1. Why do you stink when you sweat
2. upper respiratory infection includes
3. lower includes; normally sterile due to
4. Staphylococcal, Streptococcal, Neisseria, and Haemophilus spp. can be found living as normal flora in the throat. Why don’t we get sick?
5. how can we id strep?

Back 13

1. Body odor results from bacterial activity.  Your actual apocrine (sweat) gland secretions are odorless, but these glands (especially those associated with hair follicles) harbor bacteria which are smelly microorganisms!
2. nose and throat
3. larynx, trachea, bronchial tubes, and alveoli; ciliary escalator
4. Microbial antagonism
Organism produces substances that suppress or inhibit the growth of other microorganisms
Competition for same nutrients
5. Hemolysis – ability to degrade hemoglobin; lyse RBCs
Antibiotic sensitivity/resistance
Optochin
Bacitracin

Front 14

1. ability to degrade hemoglobin causing the lyisis of RBCs (3 types)
2. what is chocolate agar?
3. why is it used?

Back 14

1. hemolysis (alpha-partial hemolysis , beta- a clearing is seen around the colonies, gamma- usually white to yellowish colonies)
2. Chocolate agar (CHOC) - is a non-selective, enriched growth medium.
It contains red blood cells, which have been lysed
3. used for growing fastidious (fussy) respiratory bacteria; These bacteria need growth factors, like NAD and hematin, which are inside red blood cells;