In microbiology, the term growth usually refers to ____.
an increase in the number of microbial cells
A cell that uses an organic carbon source and obtains energy from light would be called a ____.
Nitrogen is a growth limiting nutrient for many organisms because _________.
only a few microbes can extract it from the atmosphere, but all organisms require it for amino acid and nucleotide synthesis
At temperatures higher than the maximum growth temperature for an organisms _____.
hydrogen bonds are broken, proteins are denatured, and membranes become too fluid
New cells are being produced at the same rate as other cells are dying during the _______ of growth.
Joan wants to discover a microbe capable of degrading an environmental contaminant. Which process should she use?
Which of the following types of plasmids allows a bacterial cell to kill its competitors?
Which of the following is NOT a characteristic of Okazaki fragments?
They are longer in eukaryotic cells.
Which of the following is a characteristic of prokaryotic genomes but not eukaryotic genomes?
T or F: The structure of DNA explains both its ability to encode genetic information and the way in which it is copied during cell reproduction.
RNA polymerase initiates transcription by recognizing specific nucleotide sequences called ____.
Which of the following statements concerning transcription in bacteria is FALSE?
The same RNA polymerase transcribes primer RNA mRNA, tRNA, and rRNA.
A codon is a particular combination of three nucleotides. Therefore, there are ___ of the nucleotides A, C, G, and T.
64 possible combinations
A _______ is a mutant organisms that has different nutritional requirements from the original wild-type organism.
If the codon AAA is changed to AAG, it still codes for the amino acid lysine; this is an example of a _____.
Another term for the palindromic sequence found at the ends of transposons is _______.
Natural antiseptics such as pine or clove oil are examples of antimicrobial compounds called _______.
Which of the following statements about aldehydes is FALSE?
They are used only to preserve dead tissues.
A scientist develops a new medication that is a protein compound and that must be administered by injection. Which of the following would be the most effective and safest means of preparing a sterile solution of the new medication?
Which of the following was used in the past to prevent the transmission of gonorrhea from an infected mother to her newborn?
Which of the following is used to sterilize items that should not, or cannot, be exposed to heat or what?
The endospores of which of the following microbes are used to measure the effectiveness of autoclave sterilization?
Which of the following is the most appropriate pairing of microbe and biosafety level?
Methicili-resistant staphylococcus aureus (MRSA), BSL-2
T or F: Some viruses are inactivated by the same chemical or physical agents that damage cytoplasmic membranes.
Which of the following statements concerning microbial death is FALSE?
It is not an effective means of evaluating the efficacy of antimicrobial agents.
A large percentage of antibiotics and semisynthetic drugs are produced by members of the genus ________.
Which of the following drugs specifically targets cell walls that contain arbinogalactan-mycolic acid?
were the first widely used antimetabolic antimicrobial and indirectly inhibit nucleic acid synthesis
Which of the following pathways is specifically inhibited by sulfonamides?
The conversion of PABA to Dihydrofolic acid.
Antimicrobials that block protein synthesis by binding to mRNA are _________.
antisense nucleic acids
Nucleotide or nucleoside ________ are antimicrobial agents that mimic the chemical structure of DNA building blocks.
Methicillin is an example of the B-lactam class of drugs which _____________.
inhibit cell wall synthesis
DIsruption of the normal microbiota can result in infections caused by which of the following microbes?
Candida albicans, myobacterium, and clostridium difficle
Which of the following can result when antibiotic therapy disrupts the normal microbiota?
Both pseudomembranous colitis and thrush
Which of the following is NOT a criterion by which all antimicrobial agents can be evaluated?
Their activity against cell walls
T or F: The outer membrane of Gram-negative bacteria enables many antimicrobial drugs to enter the cell more easily.
Which of the following statements concerning development of antibiotic resistance is FALSE?
Resistant cells grow more efficiently and quickly than susceptible cells.
The cooperative activity of drugs such as beta-lactam antibiotics and clavulanic acid, a B-lactamase inhibitor, is known as ______.
B- Lactamase production is an example of which of the following types of resistance?
Inactivation of the drug
It is inappropriate to prescribe antibacterial agents to treat colds or flus because __________.
these deseases are caused by viruses.