Microbiology review test three

The function of catalase is to?
Degrade peroxides
A microorganism that grows only in high pH environments is revered to as a(n)?
Alkaliphile
Most human pathogens are?
Mesophiles
Organisms that do not use oxygen but can grow in it's presence are called?
Aerotolerant anaerobes
Most strict anaerobes have the enzyme superoxide dismutase?
False
Microaerophilic growth is characterized by the need for..., while arerobic growth is characterized by the need for..?
Less than atmospheric concentrations of oxygen: atmospheric concentrations of oxygen
In the above figure, an organism with which temperature curve would grow best on a fish that swims deep in the ocean?
0-35degrees c
In a mature compost pile?
35-60 degrees
Survive autoclaving?
60-125 degrees
Which of the following enzymes do facultative anaerobes have?
Both catalas and SOD
Bacteria may be able to slow the flow of water into the cell by?
Upchucking compatible Dolores
Halophiles?
Maintain higher levels of compatible Dolores than non-halophiles
Which of the following results in sterilization ?
Autoclaving
Selective toxicity refers to?
The ability of a drug to target the infectious organism without harming the host
Which of the following is not a mode of resistance to antibiotics?
Slow entry of the drug
Individual nucleotides in a single strand DNA are held together by?
Covalent phosphdiester bonds between neighboring nucleotides
A narrow spectrum antibiotic drug?
Targets only a small subset of bacteria
Antibiotics such as sulfa drugs(sulfonamide ) work by?
Inhibition of a colic acid synthesis
Some bacteria are resistant to tetracycline because they?
Alter the ribosome
Some bacteria are resistant to penicillin because the?
Alter the B-kaftan ring
Which of the following modes of resistance often results in resistance to multiple drugs at the same time?
Pumping the drug out of the cell ( efflux pump)
Which of the following is found at the 5' end piece of DNA ( that has been cut out of a chromosome)?
Phosphate group
An antibiotic by definition is active against (targets) bacteria and viruses?
False
Antibiotics such as tetracycline work by?
Inhibition of protein synthesis
Antibiotics such as penicillin work by?
Inhibition of peptidoglycan cross linking
Which of the following methods of microbial growth control results in the destruction of DNA?
Ionizing radiation
The process of killing or removing all forms of life (all microorganisms and viruses) is referred to as what?
Sterilization
Pasteurization?
Is a method for reducing the number of disease and spoilage microbes using heat
Choose the correct order from least resistant (to methods of microbial growth control) on the left to most resistant on the right fungi, mycobacteria, endospores
A(n) ...is used on living tissue whereas a(n) ... Is used on nonliving tissue?
Antiseptic, disinfectant
Sanitization is?
A method for reducing the number of disease-causing microbes to safe public health levels
Which strand would be affected the most by UV light?
AATTAGTTC
What is the primary mode of action of phenols, phenolics, and alcohol?
Disrupts membranes
What is the primary mode of action of surface active agents such as soaps and detergents?
Decreases surface tension of water
Triclosan is a bis-phenol in many hand soaps and other consumer products. Why has its widespread household use come into question?
Because it was discovered that it works like an antibiotic rather than a general disinfectant



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