Question | Answer |
Which of the following can grow in a Petri plate on a laboratory table? | An aerobic bacterium |
This statement, "In the laboratory, a sterile inoculating loop is moved across the agar surface in a culture dish, thinning a sample and isolating individuals," describes which of the following? | Streak Plate |
Superoxide dismutase ________. | Detoxifies superoxide radicals |
The most reactive of the four toxic forms of oxygen is _______. | The Hydroxyl radical |
Microaerophiles that grow best with a high concentration of carbon dioxide in addition to a low level of oxygen are called ___________. | Capnophiles |
Which of the following is not a growth factor for various microbes? | Water |
Organisms that preferentially may thrive in icy waters are described as ________. | Psychrophiles |
Barophiles ________. | Cannot cause diseases in humans. |
Which of the following terms best describes an organism that cannot exist in the presence of oxygen? | Obligate anaerobe |
In a defined medium, __________. | The exact chemical composition of the medium is known |
Which of the following is most useful in representing population growth on a graph? | A semilogarithmic graph using a log scale on the y-axis |
Which of the following methods is best for counting fecal bacteria from a stream to determine the safety of the water for drinking? | Membrane filtration |
A Coulter counter is _________. | A device that directly counts microbes as they pass through a tube in front of an electronic detector. |
Lyophilization can be described as __________. | Freeze drying |
Quorum sensing is ___________. | The ability to respond to changes in population density. |
All cells require a source of ___________ for redox reactions. | Electrons |
A toxic form of oxygen, _________ oxygen, is molecular oxygen with electrons that have been boosted to a higher energy state. | Singlet |
All cells recycle the essential element _________ from amino acids and nucleotides. | Nitrogen |
_______ are small organic molecules that are required in minute amounts for metabolism. | Growth Factors |
The lowest temperature at which a microbe continues to metabolize is called its __________. | Minimum Growth Temperatures |
Cells that shrink in hypertonic solutions such as salt water are responding to _______ pressure. | Osmotic |
Obligate __________ exist in salt ponds because of their ability to withstand high osmotic pressure. | Halophiles |
__________ pigments protect many phototrophic organisms from photochemically produced singlet oxygen. | Carotenoid |
Microbes that reduce N2 to NH3 engage in nitrogen ____________. | Fixation |
A student observes a researcher streaking a plate numerous times, flaming the loop between streaks. The researcher is likely using the _________ method to isolate microorganisms. | Streak Plate |
Chemolithotrophs acquire electrons from _________ compounds. | Inorganic |
Which of the following is most likely the number of base pairs in a bacterial chromosomes? | |
Which of the following is a true statement concerning prokaryotic chromosomes? | |
A plasmid is _________. | |
Which of the following forms ionic bonds with Eukaryotic DNA and stabilizes it? | |
Nucleotides used in the replication of DNA _________. | |
Which of the following molecules functions as a "proofreader" for a newly replicated strand of DNA? | |
The addition of ----CH3 to a cytosine nucleotide after DNA replication is called _________. | |
In translation, the site through which tRNA molecules leave a ribosome is called the _________. | |
The Ames Test _________. | |
Which of the following methods of DNA repair involves enzymes that recognize and correct nucleotide errors in unmethylated strands of DNA? | |
Which of the following is NOT a mechanism of natural genetic transfer and recombination? | |
Cells that have the ability to take up DNA from their environment are said to be ___________. | |
Which of the following statements is true? | |
Which of the following are called "jumping genes"? | |
Although two cells are totally unrelated, one cell receives DNA from the other cell and incorporates this new DNA into its chromosome. This process is __________. | |
Transcription produces ___________. | |
A nucleotide is composed of ____________. | |
In DNA, adenine forms __________ hydrogen bonds with ____________. | |
A sequence of nucleotides formed during replication of lagging DNA strand is _________. | |
Which of the following is NOT part of an operon? | |
Repressible operons are important in regulating prokaryotic __________. | |
Which of the following is part of each molecule of mRNA? | |
Ligase plays a major role in ___________. | |
Before mutations can affect a population permanently, they must be ______. | |
The trp operon is repressible. This means it is usually ________ and is directly controlled by ___________. | |
The three steps in RNA transcription are ____________, _____________, and ____________. | Initiation of transcriptions, Elongation of the RNA transcript, Termination of transcription |
A triplet of mRNA nucleotides that specifies a particular amino acid is called a __________. | codon |
Three effects of point mutations are ___________, _____________, and ______________. | Silence, Missense, Nonsense |
Insertions and deletions in the genetic code are also called _______ mutations. | |
An operon consists of _________, __________, and ___________ and is associated with a regulatory gene. | |
In general, __________ operons are inactive until the substrate of their genes' polypeptides is present. | |
A daughter DNA molecule is composed of one original strand and one new strand because DNA replication is ___________. | |
A gene for antibiotic resistance can move horizontally among bacterial cells by __________, __________, and _____________. | |
___________ are nucleotide sequences containing palindromes and genes for proteins that cut DNA strands. | |
_________ _________ is a recombination event that occurs during gamete formation in eukaryotes. | |
__________ RNA carries amino acids. | |
_________ RNA and __________ RNA are antisense; that is, they are complementary to another nucleic acid molecule. | |