Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
40 Cards in this Set
- Front
- Back
Obligate anaerobes have enzymes such as superoxide dismutase to protect them from the damaging effects of oxygen |
false |
|
Nitrogen fixation is a process that occurs in all bacteria |
false |
|
thermoduric mesophiles are often responsible for spoilage of improperly canned foods |
true |
|
Serial dilution can be used in combination with pour plates as a method for isolating pure cultures |
true |
|
the only effective way to store bacterial cultures for short periods of time is to arrest their metabolism by freezing |
false |
|
Quorum sensing is involved in the development and propagation of a biofilm |
true |
|
An obligate anaerobe can be cultured in a candle jar |
false |
|
Agar is a useful compound in the microbiology lab because it is an excellent nutrient for bacteria |
false |
|
A selective medium can be formulated either by including inhibitory chemical substances or by leaving out a single crucial nutrient |
true |
|
In spectrophotometry, 40% light transmission is the same thing as 60% absorbance of light |
true |
|
Prokaryotic cells are diploid |
false |
|
A chemical is reported to inhibit bacterial replication. Bacterial cells are placed in medium with all nutrients necessary for replication. The chemical is added to the culture, and after a half hour an extract of the DNA is prepared. A significant percentage of the DNA is in pieces about 1000 to 2000 bases in length. The results are consistent with the chemical blocking the function of DNA ligase |
true |
|
Pyrimidine dimers are severe mutations because cells have few mechanisms for repairing them |
false |
|
Most bacteria have a natural ability to take up DNA from their environment |
false |
|
The structure of DNA explains both its ability to encode genetic information and the way in which it is copied during cell reproduction |
true |
|
DNA, which is negatively charged, wraps around positively charged histones as part of the packaging of eukaryotic chromosomes |
true |
|
Bidirectional replication means that each strand of a DNA molecule is replicated in the opposite direction from the other |
false |
|
The phenotype of an organism reflects only part of its genotype |
true |
|
In generalized transduction, viruses carry random DNA sequences from one cell to another |
true |
|
DNA polymerase III participates in the dark repair mechanism of DNA mutation repair |
false |
|
Gene therapy for human genetic diseases has not been successful yet |
false |
|
Reverse transcriptase synthesizes a DNA molecule from an RNA template |
true |
|
The goals of recombinant DNA technology include production of new organisms with useful combinationsof traits |
true |
|
Restriction enzymes are useful only on synthetic DNA's |
false |
|
Under ideal conditions, the number of DNA molecules produced during PCR increases exponentially |
true |
|
Sticky-end fragments generated by EcoRI will hydrogen bond to any other sticky-end sequence |
false |
|
A collection of bacterial clones each of which contains a portion of the gene sequences of an organism is known as a microarray of that organism's genome |
false |
|
Southern blotting is a technique that can be used to identify microbes that cannot be cultured |
true |
|
DNA fingerprinting produces a unique banding pattern of DNA fragments for comparison with other DNA samples |
true |
|
A subunit vaccine is prepared by extensive manipulation of the genome of the pathogen |
false |
|
Removal of microbes from the skin is antisepsis |
true |
|
Some viruses are inactivated by the same chemical or physical agents that damage cytoplasmic membranes |
true |
|
Refrigeration is an effective germicidal method |
false |
|
Antimicrobial agents usually work best at high temperatures and high pH levels |
false |
|
The phenol coefficient is one of the most widely used measurements of an antimicrobial agent's effectiveness |
false |
|
No chemical or antimicrobial agents inactivate prions |
false |
|
The decimal reduction time is the time required to kill all the microbes in a given sample |
false |
|
Slow freezing is more damaging to microbial cells than quick freezing |
true |
|
The pH conditions under which a chemical disinfectant is used do not alter its efficacy |
false |
|
By themselves, soaps have only degerming activity, not antimicrobial activity |
true |