Micro Exam 2 (Ch. 5,7 &8)

A chemical used to control microbial growth on inanimate objects is called a(n) -disinfectant. -antiseptic. -microbiocidal. -microbiostatic. -antibacterial agent.

Disinfectant

________ is when the fertility plasmid merges with the bacterial cell's chromosome and ceases to be an independent plasmid in the cytoplasm. - Recombination - Transformation - Transduction - Conjugation - Transfection

Recombination

Consider the following sequences: the first is an original DNA sequence and the second is an altered sequence. What type of mutation does the second sequence represent?5'-AAT GCC GAT-3'5'-AAT CCC GAT-3' - Frameshift mutation - Reversion mutation - Substitution mutation - Deletion mutation - Insertion mutation

Substitution mutation

Which of the following terms refers to bacteria reproducing asexually, creating two daughter cells by dividing the cell in half? - budding - binary fission - sporulation - conidia - hypha

Binary fission

________ mutagens are agents that can introduce genetic change through recombination. - Biological - Chemical - Physical - Frameshift - Organic

Biological

Frameshift mutations can do all of the following except - insert or delete a DNA base. - cause the DNA to revert back to the original sequence. - change the protein's amino acid sequence. - render the protein useless to the cell. - insert or eliminate an amino acid.

cause the DNA to revert back to the original sequence

Which type of organism gets energy from breaking down nutrients and uses CO2 as a carbon source? -photoautotroph -photoheterotroph -chemoautotroph -chemoheterotroph -lithotroph

chemoautotroph

Bacteria that live in deep ocean volcanic vents form the base of an ecosystem that exists without light. They obtain electrons from hydrogen sulfide compounds dissolved in the vent water, and synthesize sugars from carbon, hydrogen, and oxygen. The bacteria would be classified as -chemoautotrophs. -chemoheterotrophs. -photochemoautotrophs. -photoautotrophs. -photoheterotrophs.

chemoautotrophs.

How would humans (and many microbes that inhabit the human body) be best described in terms of nutritional requirements? -photoautotroph -photoheterotroph -chemoautotroph -chemoheterotroph -Humans are not microorganisms, so these categories do not apply.

chemoheterotroph

Transformation requires cells to be in direct contact with each other in order for DNA exchange to occur. - True - False

false

Usually, a single biochemical test is all that is needed to identify an unknown microbial sample. -true -false

false

Which of the following cell-counting methods is capable of differentiating between living and dead cells? -microscopic count -Coulter counter -flow cytometer -turbidity measurement -dry weight

flow cytometer

Which of the following statements is false? - There are hundreds of amino acids found in nature. - There are 22 amino acids that are genetically encoded by codons. - Four amino acids are considered nonstandard. - In some species, one stop codon has been swapped out for one of the nonstandard amino acids. - Nonstandard amino acids are found in prokaryotes and eukaryotes.

four amino acids are considered nonstandard.

Which of the following is not an environmental factor that would affect the growth of E. coli? -temperature -availability of nutrients -concentration of other bacteria -antibiotics produced from other bacterial species -generation time of E. coli

generation time of E. coli

In general, the more complex an organism is, the more ________ it has. - chromosomes - genes - cytoplasm - mutations - histones

genes

Which of the following terms refers to the genetic makeup of an organism? - phenotype - genotype - heritable - primosome - RNA

genotype

Which of the following pathways are operational in a cell growing via fermentation? -glycolysis only -intermediate step only -Krebs cycle only -glycolysis and intermediate step only -glycolysis, intermediate step, and the Krebs cycle

glycolysis only

Which of the following terms refers to microbes that thrive in high-salt environments? -neutralophiles -barophiles -halophiles -psychrophiles -acidophiles

halophiles

Which of the following pH classifications make up most of the pathogens we know today? -acidophiles -neutralophiles -alkaliphiles -barophiles -psychrophiles

neutralophiles

Which of the following methods would surgical staff use to disinfect surfaces in operating rooms? -ionizing radiation -non-ionizing radiation -autoclaving -gamma ray radiation -x-ray radiation

non-ionizing radiation

Where can the DNA of prokaryotic cells be found? - nucleoid - nucleus - nucleolus - around histones - in numerous linear chromosomes

nucleoid

Microbes that primarily infect the lungs are likely to be classified as which of the following? -obligate aerobe or facultative anaerobe -obligate anaerobe or facultative anaerobe -microaerophile -aerotolerant anaerobe -obligate anaerobe

obligate aerobe or facultative anaerobe

How does transformation differ from conjugation? - Transformation involves a pilus. - Transformation requires only fresh DNA be used. - Transformation takes up DNA from the environment. - Transformation requires DNA to be on a plasmid. - Transformation can only exchange DNA between bacteria of the same species.

Transformation takes up DNA from the environment.

An unknown organism is being tested for the ability to ferment various sugars. The pH indicator phenol red is added to a fermentation broth containing sucrose. Phenol red indicator is pink at a pH above 8, red at pH 7, and yellow at a pH below 7. After incubation, if the organism can ferment sucrose, what color will the fermentation broth be? -Red, because fermentation of sucrose will result in a neutral pH. -Red, because fermentation of sucrose will produce acidic products. -Yellow, because fermentation of sucrose will result in the production of basic products. -Yellow, because fermentation of sucrose will result in the production of acidic products. -Pink, because fermentation of sucrose will result in the production of basic products

Yellow, because fermentation of sucrose will result in the production of acidic products.

Anabolic reactions -are endergonic. -involve dehydration synthesis. -involve breaking down larger molecules into smaller molecules. -are endergonic and involve dehydration synthesis. -are endergonic and involve breaking down larger molecules into smaller molecules.

are endergonic and involve dehydration synthesis

Catabolic reactions -are endergonic. -are hydrolytic. -involve breaking down larger molecules into smaller molecules. -are endergonic and are hydrolytic. -are hydrolytic and involve breaking down larger molecules into smaller molecules

are hydrolytic and involve breaking down larger molecules into smaller molecules

Key mechanisms of horizontal gene transfer include all of the following except - conjugation. - transformation. - transduction. - reproduction. - transposons.

reproduction

Which type of media has ingredients that foster the growth of certain bacteria while suppressing the growth of others? -differential -selective -complex -defined -synthetic

selective

Naturally occurring mutations are often referred to as ________ mutations. - deleterious - insertion - spontaneous - neutral - unnoticed

spontaneous

In which growth phase do bacteria produce antibiotics and endospores? -death phase -lag phase -log phase -stationary phase -acculturation phase

stationary phase

When bacteria use budding for reproduction, -the daughter cells are not genetically identical. -the daughter cells are not equal in size. -the daughter cells are produced by sexual reproduction. -conidia form long hyphae extensions. -the bud forms as a way to survive unfavorable growth conditions.

the daughter cells are not equal in size

A molecule that is oxidized has less energy than one that is reduced. -true -false

true

A pure culture of bacteria grown in the lab does not offer a fully realistic representation of how microbes normally live and grow in nature. -true -false

true

A reversion mutation is when a base-substitution mutation is changed back to the original DNA sequence. - True - False

true

An organism's genotype influences its phenotype. - True - False

true

By the end of the Krebs cycle, every carbon originally in glucose is converted into carbon dioxide. -true -false

true

Catabolic reactions are hydrolytic and exergonic while anabolic reactions are biosynthetic and endergonic. -true -false

true

Cells harvest energy from nutrients by stripping electrons from them. In other words, the nutrients are oxidized. -true -false

true

In the death phase of a closed pure batch system a small number of the cells survive by adapting to the new waste-filled environment and by feeding off dead cells. -true -false

true

Many microbes have evolved ways to detoxify reactive oxygen species so that they can safely use oxygen in their metabolism. -true -false

true

Many mutagens cause a rate of mutation that promotes the development of cancers; such mutagens are called carcinogens. - True - False

true

Which of the following is an indirect cell-counting method? -microscopic count -Coulter counter -flow cytometer -turbidity measurement -viable plate count

turbidity measurement

Which of the following nitrogen bases is found only in RNA and NOT in DNA? - thymine - cytosine - guanine - adenine - uracil

uracil

Mycobacterium tuberculosis are grown for 80 hours. During that time, they go through four generations of growth. What is the generation time? -10 hours -20 hours -40 hours -20 minutes -60 minutes

20 hours

A water treatment plant is testing for E. coli and other coliforms using Eosin-Methylene blue (EMB) media that will produce metallic green colonies in the presence of coliform bacteria. After performing serial dilutions and spread-plating 1 ml of each of the dilutions on the EMB, the 1:1000 dilution plate produced 130 total colonies, with 85 metallic green colonies. How many coliforms (in CFU/ml) were in the original water sample? -130 CFU/ml -130,000 CFU/ml -85 CFU/ml -8,500 CFU/ml -85, 000 CFU/ml

85,000 CFU/ml

Which facts about enzymes are not visualized in this figure? -Enzymes are not consumed or permanently changed in a reaction. -A substrate binds to an enzyme at the active site as described by the "induced-fit" model. -Specific products are generated. -A cofactor is often required for enzyme activity. -The substrate is converted to products after going through the transition state.

A cofactor is often required for enzyme activity.

Which of the following statements best describes how catabolic and anabolic reactions depend upon each other? -Anabolic reactions split bigger molecules into smaller components, which are in turn used by catabolic reactions to build more complex molecules. -Catabolic reactions split bigger molecules into smaller components which are then used by anabolic reactions to build more complex molecules. -Catabolic reactions release energy which is used by anabolic reactions. -Anabolic reactions split bigger molecules into smaller components, which are in turn used by catabolic reactions to build more complex molecules AND catabolic reactions release energy which is used by anabolic reactions. -Catabolic reactions split bigger molecules into smaller components which are then used by anabolic reactions to build more complex molecules AND catabolic reactions release energy which is used by anabolic reactions.

Catabolic reactions split bigger molecules into smaller components which are then used by anabolic reactions to build more complex molecules AND catabolic reactions release energy which is used by anabolic reactions.

Which of the following statements about conjugation is false? - Conjugation is sexual reproduction for bacteria. - In conjugation a bacterium carries a fertility plasmid. - In conjugation a bacterium forms a small hollow tube called a pilus. - In conjugation a bacterium attaches to a neighboring bacterial cell that lacks a fertility plasmid. - Conjugation can be a problem because fertility plasmids often carry genes that endow cells with drug resistance or the ability to produce toxins.

Conjugation is sexual reproduction for bacteria

What is the relationship between the ATP-ADP cycle and catabolic and anabolic reactions? -Energy released from catabolic reactions is used to recharge ADP back to ATP. Then the energy needed for anabolic reactions is released by breaking ATP down to ADP. -Energy released from anabolic reactions is used to recharge ADP back to ATP. Then the energy needed for catabolic reactions is released by breaking ATP down to ADP. -Energy released from catabolic reactions is used to break ATP down to ADP. -Then the energy needed for anabolic reactions is released by to recharging ADP back to ATP. -Catabolic reactions require energy, which is provided by anabolic reactions. ADP is recharged to ATP by energy from anabolic reactions. -There is no relationship between the ATP-ADP cycle and catabolic and anabolic reactions.

Energy released from catabolic reactions is used to recharge ADP back to ATP. Then the energy needed for anabolic reactions is released by breaking ATP down to ADP.

Which of the following statements about plasmids is false? - Plasmids are nonchromosomal DNA segments found in bacteria and a number of eukaryotic cells. - Plasmids are commonly shared among cells by horizontal gene transfer mechanisms. - Plasmids are easily manipulated in the laboratory. - Molecular biologists often use plasmids to generate cell lines that make useful products for medical applications. - If present, plasmids are always essential to cell survival.

If present, plasmids are always essential to cell survival.

Which of the following terms is correctly matched with its description? - Substitution mutations: Occur when an incorrect amino acid is added. - Insertion mutations: Occur when a cell adds one or more nucleotides to its genome sequence. - Deletion mutations: Occur when one or more amino acids are removed from a protein sequence. - Point mutations: Occur when an incorrect carbohydrate is added. - Substitution mutations: Occur when an incorrect fatty acid is added.

Insertion mutations: Occur when a cell adds one or more nucleotides to its genome sequence.

________ RNA carries a genetic message in triplet code (codons) and is translated to build a protein. - Messenger - Transfer - Ribosomal - Alternative - Junk

Messenger

Which of the following statements about mutations is false? - A mutation is a change in the genetic material of a cell or virus. - Mutations are essential to evolution within species. - A mutation in a single-celled organism is more likely to be passed to daughter cells than a multicellular organism. - Multicellular organisms evolve faster than unicellular organisms. - Mutations are essential to variation within species.

Multicellular organisms evolve faster than unicellular organisms

A microbiologist is analyzing a sample collected from the ocean floor. Two new organisms are discovered. During DNA analysis, it is determined that Organism 1 has 3 chromosomes, while Organism 2 has 12 chromosomes. Which of the following conclusions can be made from this research? - Organism 1 is more complex. - Organism 2 is more complex. - Organism 1 is most likely a unicellular organism, while Organism 2 is a multicellular organism. - Organism 1 is most likely a multicellular organism, while Organism 2 is a unicellular organism. - No conclusion can be made regarding overall complexity of the newly isolated organisms based on number of chromosomes.

No conclusion can be made regarding overall complexity of the newly isolated organisms based on number of chromosomes.

Which category of biochemical tests is incorrectly matched with its description? -Amino acid catabolism tests: Detect specific enzymes involved in catabolism of amino acids -Exoenzyme tests: Detect enzymes involved in extra-cellular breakdown of macromolecules -Fermentation tests: Detects various fermentation end-products or specific pathways -Oxidase and catalase tests: Identifies the presence of enzymes related to anaerobic respiratory chains -Rapid identification techniques: Provide a semi-automated process of running multiple types of tests with a single inoculation

Oxidase and catalase tests: Identifies the presence of enzymes related to anaerobic respiratory chains

The graph shows enzyme activity as a function of temperature for a mesophilic microbe. How would you predict that the graph would change if the organism was a psychrophile (an organism that thrives at low temperatures)? -The graph would be similar, but would be shifted toward the left. -The graph would be similar, but would be shifted toward the right. -The graph would be wider (extended further both left and right) but the peak would be lower. -The graph would not peak then drop off, but would continue rising indefinitely. -The graph would be a horizontal straight line.

The graph would be similar, but would be shifted toward the left.

The graph shows enzyme activity as a function of temperature for a mesophilic microbe. How would you predict that the graph would change if the organism was a thermophile (an organism that thrives at high temperatures)? -The graph would be similar, but would be shifted toward the left. -The graph would be similar, but would be shifted toward the right. -The graph would be wider (extended further both left and right) but the peak would be lower. -The graph would not peak then drop off, but would continue rising indefinitely. -The graph would be a horizontal straight line.

The graph would be similar, but would be shifted toward the right.

In Griffith's experiments, mice that were exposed to both killed encapsulated bacteria and live nonencapsulated bacteria died even though killed encapsulated bacteria alone or live nonencapsulated bacteria alone did not result in illness. What is the best way to explain this result? - A bacteriophage used specialized transduction to shuttle the capsule-making genes into the nonencapsulated bacteria. - The live nonencapsulated bacteria picked up the capsule-making genes from the environment in the process of transformation. - The live nonencapsulated bacteria underwent a reversion mutation to restore the function of capsule-making genes. - The killed encapsulated bacteria released toxins that killed the mice. - Transposons allowed the capsule-making genes to "jump" from an inactive part to an active part of the genome.

The live nonencapsulated bacteria picked up the capsule-making genes from the environment in the process of transformation.

How do halophiles combat osmotic stress? -They keep a high concentration of organic materials and ions in their cytoplasm. -They enrich their plasma membrane with basic compounds to attract OH- ions to their cell surface. -They use proton pumps to export excess protons from the cytoplasm. -They build special monolayer plasma membranes. -They use plasma membrane lipids that are highly branched and saturated.

They keep a high concentration of organic materials and ions in their cytoplasm

Oxidation of nutrients by cells results in -a release of energy, which can be used to recharge ADP to ATP. -a release of energy, which is released by converting ATP to ADP. -a requirement for energy which can be used to recharge ADP to ATP. -a requirement for energy which can be obtained by converting ATP to ADP. -either a release or a requirement for energy depending on what type of nutrient is available.

a release of energy, which can be used to recharge ADP to ATP.

Which of the following pH classifications would be able to grow in a pickle jar with vinegar? -acidophiles -neutralophiles -alkaliphiles -barophiles -psychrophiles

acidophiles

A pathway that functions simultaneously in both anabolism and catabolism is termed -allosteric. -amphibolic. -biosynthetic. -cyclic. -redox.

amphibolic.

Which structural and functional feature(s) listed are key to an enzyme's activity? -consumed each time a reaction takes place -consists of a three-dimensional protein structure that interacts with a substrate in a fixed "lock-and-key" model -contains an active site where the enzyme can interact with a specific substrate -consumed each time a reaction takes place AND consists of a three-dimensional protein structure that interacts with a substrate in a fixed "lock-and-key" model -consumed each time a reaction takes place AND contains an active site where the enzyme can interact with a specific substrate

contains an active site where the enzyme can interact with a specific substrate

The genetic code... - has 60 codons. - encodes for 18 amino acids. - contains sense codons and nonsense codons. - uses a quartet code to encode the codons. - relies on codons made up of DNA.

contains sense codons and nonsense codons

Which of the following methods do alkaliphiles use to survive in their environments? -enrich their plasma membrane with acidic compounds to attract H+ ions to their cell surface -enrich their plasma membrane with basic compounds to attract OH- ions to their cell surface -use proton pumps to export excess protons from the cytoplasm -build special monolayer plasma membranes -use plasma membrane lipids that are highly branched and saturated

enrich their plasma membrane with acidic compounds to attract H+ ions to their cell surface

Enzymes are necessary for cells because -enzymes allow chemical reactions to take place that would otherwise be impossible. -enzymes slow down chemical reactions that would otherwise occur too quickly to facilitate life. -enzymes allow chemical reactions to occur under physiological conditions. -enzymes allow chemical reactions to occur quickly enough to facilitate life. -enzymes allow chemical reactions to occur under physiological conditions AND quickly enough to facilitate life.

enzymes allow chemical reactions to occur under physiological conditions AND quickly enough to facilitate life.

Nutrients that a cell needs to build new cells and make up a bulk of a cell's dry weight are called -micronutrients. -trace nutrients. -essential nutrients. -tiny nutrients. -small nutrients

essential nutrients

In order to harvest energy from polysaccharides, lipids or proteins, cells must use ________ to break down these large macromolecules extracellularly before bringing them into the cell. -beta-oxidation -deamination -Entner-Doudoroff pathway -exoenzymes -glycogenesis

exoenzymes

Which group of microbes prefers using oxygen but can survive without it? -obligate aerobe -obligate anaerobe -microaerophile -aerotolerant anaerobe -facultative anaerobe

facultative anaerobe

Staphylococcus aureus tolerates higher solute concentrations but doesn't grow especially well in them. Therefore, it is called a -halo-psychrophile. -halo-alkaliphile. -obligate halophile. -halo-thermophile. -facultative halophile

facultative halophile

A bacterial culture which is growing under conditions that only allow for fermentation will grow at the same rate as a culture of the same species growing under conditions which allow for aerobic cellular respiration, all other conditions being identical. -true -false

false

Bacterial spore formation is a type of sexual reproduction. -True -False

false

Chemoheterotrophs (or Photoheterotrophs) use an inorganic carbon source. -true -false

false

Disinfectants are applied to living tissue such as skin. -true -false

false

Phenols are commonly used in hospitals to sterilize critical equipment. -true -false

false

Of the following fermentation pathways, which can be carried out by human muscle cells? -alcoholic -butanediol -lactic acid: heterolactic -lactic acid: homolactic -mixed acid

lactic acid: homolactic

In which growth phase do bacteria adjust to their environment and grow little, if any? -habituation phase -lag phase -log phase -stationary phase -acculturation phase

lag phase

In which growth phase do bacteria grow exponentially? - habituation phase - lag phase -log phase -stationary phase -acculturation phase

log phase

Which temperature group are most pathogens associated with? -psychrophiles -psychrotrophs -mesophiles -thermophiles -extreme thermophiles

mesophiles

The term ________ includes both the chemical reactions that organisms use to break down substances to release energy, as well as the reactions that use released energy to build new substances. -anabolism -biosynthesis -catabolism -metabolism -oxidation-reduction

metabolism

Besides biochemical tests, which techniques are also useful for identifying a bacterial specimen? -microscopy -molecular genetics techniques -observation of general culture characteristics -microscopy and observation of general culture characteristics -microscopy and molecular genetics techniques and observation of general culture characteristics

microscopy and molecular genetics techniques and observation of general culture characteristics

Which term represents the temperature at which bacteria grow the fastest? -minimum temperature -maximum temperature -optimal temperature -thermal growth point -human body temperature

optimal temperature

Enzymes can lower the activation energy of a chemical reaction by -properly positioning reactants. -stabilizing the transition state. -raising the temperature so that reactants collide more forcefully. -properly positioning reactants AND stabilizing the transition state. -properly positioning reactants AND raising the temperature so that reactants collide more forcefully.

properly positioning reactants AND stabilizing the transition state.

Which of the following types of organisms is associated with foodborne illness? -psychrophiles -psychrotrophs -mesophiles -thermophiles -extreme thermophiles

psychrotrophs

A patient sample from an infected wound was cultured on medium containing high salt so that only halophilic organisms could grow. In addition, the medium contains mannitol (a sugar alcohol) and phenol red dye that indicates whether or not fermentation of mannitol has taken place by changing to a yellow color as the pH drops. This type of media would best be described as -selective medium. -differential medium. -enrichment medium. -selective AND differential medium. -selective AND enrichment medium

selective AND differential medium

A ________ mutation does not change the amino acid sequence of a protein. - deletion - missense - nonsense - silent - frameshift

silent

In the typical ATP-ADP cycle, which part of the ATP molecule is removed when energy is released and added back when energy is stored? -adenine -ribose -the terminal phosphate group -the terminal two phosphate groups -all three phosphate groups

the terminal phosphate group

The minimum temperature needed to kill all microbes in a sample within ten minutes is called the -thermal death time. -thermal death point. -decimal reduction time. -essential reduction point. -critical death time.

thermal death point

Biochemical tests are useful to microbiology because -they can be used to identify microbes. -they can be used to detect metabolic end-products, intermediates, or particular enzymes. -they can be used to identify potential pathogens in clinical samples. -they can be used to identify microbes AND to identify potential pathogens in clinical samples. -they can be used to identify microbes AND to identify potential pathogens in clinical samples AND to detect metabolic end-products, intermediates, or particular enzymes.

they can be used to identify microbes AND to identify potential pathogens in clinical samples AND to detect metabolic end-products, intermediates, or particular enzymes

What is the purpose of the streak plate technique? -to determine the concentration of a microbial sample -to identify the best temperature for growing a particular microbe -to identify the correct concentration of nutrients needed for optimal bacterial growth -to obtain a pure culture from a mixed or unknown source -to ascertain the age of a particular culture

to obtain a pure culture from a mixed or unknown source

When would a microbiologist want to use broth media? -when growing large batches of microbes -when isolating colonies -when observing specific culture characteristics -when performing the streak plate isolation technique -when testing for motility

when growing large batches of microbes