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Micro Lecture test 2
Chapter 7, 11, 12
Question | Answer |
---|---|
This is the process of acquiring chemicals from the environment to be used for cellular activities | Nutrition |
___ is required for the production of the amino groups of all amino acids, and nucleotides | Nitrogen |
organisms that feed on dead organisms for nutrients are called | Saprobes |
the majority of human pathogens fall into the group called ___ | Mesophile |
Toxic hydrogen peroxide in some bacteria can be broken down into water and oxygen by the enzyme ___ | Catalase |
The toxic superoxide ion is converted to harmless oxygen by two enzymes ___ | Superoxide dimutase and catalase |
A halophile would grow best in ____ | Salt lakes |
Microbes in a biofilm use quorum sensing to___ | Assess the size of a particular microbial population attach to surfaces |
The phase kof the bacterial growth curve in which newly inoculated cells are adjusting to their new environment, metabolizing but not growing is the ____ | Lag Phase |
The phase of the bacterial growth curve that shows the maximum rate of cell division is the ___ | Exponential (log) phase |
Phosphorus is one of the major elements needed in larger quantities by microorganisms T or F | True |
Lithoautotrophs use inorganic nutrients for carbon and energy sources T or F | True |
A microorganism that has an optimum growth temperature of 37 degrees Celsius, but can survive short exposure to high temperatures is called ____ | Thermoduric microbe |
The term facultative refers to ___ | The ability to exists in more than one condition, for example without oxygen |
Bacteria like Staphyloccus aureus can tolerate salt up to a certain point, higher than most normal pathogens. This means this bacteria is a ____ | Facultative halophile |
The production of antibiotics is a form of antagonism called ____ | Antibiosis |
A viable count technique is a means establishing a growth curve or pattern by sampling a culture over a given period of time and counting cells (colonies) T or F | True |
In the viable plate count method, a measured volume of a culture is evenly spread across an agar surface and incubated. Each __ represents one __ from the original sample | colony; cell |
Proteins, carbohydrates, and lipids would be considered | macronutrients |
Growth factors | cannot be synthesized by the organism |
Obligate parasites are unable to live outside a living cell T or F | True |
Which of the following promotes the fastest replication of microbes? | optimum temperature |
The term obligate refers to | existing in a very narrow niche, (has to exist in that condition) |
The term aerotolerant anaerobe refers to an organism that | does not use oxygen but tolerates it |
Which of the tollowing might grow in the very low pH of your stomach? | acidophile |
This is a general term for when two organisms live together in a close partnership | symbiosis |
This method of copying DNA or RNA can actually be used to detect and measure the amounts of microbes in a sample without culturing them | qPCR or PCR |
Measuring growth by counting a special slide with a premeasured grid is known as ___ | direct cell count |
Scrubbing or immersing the skin in chemicals to reduce the numbers of microbes on the skin is | degermation |
Radiation typically damages Nucleic Acids. This means it damages | DNA and RINA |
Dry heat __ | Typically takes longer to effect bacteria than moist heat |
Cold sterilization is when ionizing ___ is used as an effective alternative for sterilizing materials that would be sensitive to heat or sterilizing chemicals | radiation |
Ethylene oxide is __ | A gaseous sterilant. |
The first modern antimicrobial drugs were sulfa drugs T or F | True |
Inorganic nutrients typically contain carbon and are produced by living things T or F | False |
All __ consist of a thiazolidine ring, a beta-lactam ring, and an R group | Penicillins |
Clavulanic acid inhibits | Beta-lactamase activity |
Heavy metal compounds like mercury and silver are oligodynamic, meaning they are toxic in minute quantities T or F | True |
Which of the following is not one of the toxic forms of oxygen that can damage the cell? | Water |
__ would most likely have a optimum growth temperature of 37 degrees Celsius | Mesophile |
Sterilization is achieved by | Steam autoclave |
The us eof chemical agents directly on exposed body surfaces to destroy or inhibit vegetative pathogens is __ | Antisepsis |
__ heat is more rapidly effective and efficient compared to __ | Moist; dry |
Chemicals like triclosan are being removed from antiseptic product like soaps because of possible long-term health effects, what group of antimicrobial chemicals does triclosan belong to? | Phenolics |
Which antimicrobial methods does not sterilize | Pasteurization |
An organism that needs oxygen to grow Is a(n) | obligate aerobe |
Each of the following is a target of antimicrobial agents except | cytoplasm |
___ radiation excites atoms to a higher energy state within molecules such as DNA, which leads to the formation of pyrimidine dimers | Ultraviolet |
Heavy metal compounds like mercury and silver are oligodynamic, meaning they are toxic in minute quantities T or F | True |
The Kirby-Bauer test uses an agar surface seeded with the test bacterium, and small discs containing a specific concentration T or F | True |
All ___ consist of a thiazolidine ring, a beta-lactam ring, and an R group | penicillins |
Clavulanic acid inhibits | beta-lactamase activity |
An organism that needs oxygen to grow is called | Obligate aerobe |
If a microbe is exposed to a temperature below its minimum temperature, it is quickly killed? T or f | False |
The Calvin cycle in photosynthesis is exactly like the Krebs cycle in that it oxidizes a carbohydrate into co2 t or f | False |
A microorganism that has an optimum growth temperature of 37°C, but can survive exposure to high temps is called | thermoduric microbe |
the following temp ranges would be a "danger zone" for food to be at for a considerable length of time? | 20-40°C |
Microbes in a biofilm use quorum sensing to | assess the size of a particular microbial population |
What is the difference between mutualism and synergism? | In mutualism, the organisms are dependent upon each other |
Organisms that grow at 0°C and have optimum growth temperatures of 15°C or lower are called | psychrophiles |
When microbes live independently but cooperate and share nutrients, it is called | synergism |
When microbes are in a close nutritional relationship and one benefits but the other is not harmed harmed, it is called | commensalism |
These microbes grow better at a higher concentration of carbon dioxide | capnophiles |
During which phase of growth would bacteria be most sensitive to antibiotics? | exponential (log) |
Nutrients that encourage the growth of beneficial microbes in the intestines are known as | prebiotics |
A large percentage of antibiotics in the United States are for livestock use. Why is this problematic for Us? | Resistant bacteria grow in the animals and may then be passed to humans |
Antibiotics like penicillin will shorten the duration of the common colds or f | False |
Bacteria can have a natural resistance to a drug to which they have never been exposed t or f | True |
Some bacteria prevent antibiotics from entering by altering the structure of their ribosomes in the outer membrane t or f | False |
The cellular basis for bacterial resistance to antimicrobials include | synthesis of enzymes that alter drug structure |
possible mechanisms of antiviral drugs | -blocking DNA replication, and/or transcription and translation -blocking maturation -blocking entry/penetration |
Alexander Fleming found that the Staphylococcus was being inhibited by the Penicillium mold t or f | True |
Kirby-Bauer test uses an agar surface seeded with the test bacterium, and small discs containing a specific concentration of several drugs are placed on the surface t or f | True |
DNA ___ is targeted by certain drugs such as the fluoroquinolones, and is prevented from uncoiling DNA | Gyrase |
Sulfonamides are analogs of PABA and, as a result, they inhibit __ synthesis | Folic acid |
A large percentage of all sales of medically important antibiotics in the United States are for livestock use. Why is this problematic for humans? | Resistant bacteria grow in the animals and may then be passed to humans |
Bacteria can have a natural resistance to a drug to which they have never been exposed t or f | True |
what happens in Osmotic pressure as an antimicrobial agent | hypertonic environments draws water out of the cell, causing plasmolysis |
Enzyme that will allow some bacteria to be resistant to many penicillins is called | penicillinase |
Polymixins are narrow-spectrum peptide antibiotics that attack DNA and denature it T or F | False |
In a normal growth curve, the curve dips downwards in the | death phase |
Drugs that act by mimicking the normal substrate of an enzyme, thereby blocking its active site, are called | competitive inhibitors |
The multidrug resistant pumps in many bacterial cell membranes function by | removing the drug from the cell when it enters |
Antibiotics that disrupt bacterial ribosomes can also affect | eukaryotic mitochondrial ribosomes |
Bacteriostatic agents kill bacterial cells T or F | False |
Each affect cell walls except -penicillin -vancomycin -erythromycin -cephalosporin | erythromycin (a macrolide) |