Microbio Exam 1 questions

RQ 5: The following groups of bacteria are considered chemolithotrophs since they are capable of gaining energy from inorganic sources: A. Hydrogen bacteria B. Sulfur bacteria C. Nitrifying bacteria D. Iron bacteria E. All of the above

E. All of the above

RQ 2: A prokaryotic chromosome is typically a single, linear double-stranded DNA molecule that contains all the essential genetic information needed by the cell. True False

False

RQ 2: HAEMOPHILUS INFLUENZAE is a Gram-negative coccobacillus. If you looked at a Gram-stained culture using a light microscope, you would expect to see: a. pink, very short rods b. pink spheres c. purple spheres d. purple, very long rods

a. pink, very short rods

RQ 1: A process used in transmission electron microscopy that can be used to view internal cellular details but which can distort the cell is known as: A. Cryo-electron tomography B. Thin-sectioning C. Freeze fracturing

B. Thin sectioning

RQ 1: A negative stain technique: A. Can be used to see flagella with the light microscope B. Uses acidic dyes and reveals bacterial capsules C. Allows you to visualize interior bacterial cell structures D. Uses basic dyes

B. Uses acidic dyes and reveals bacterial capsules

RQ 3: A site on an enzyme other than the active site that can bind molecules and influence the shape of the active site is referred to as a(n) A. amphibolic site. B. allosteric site. C. transition state site. D. inactive site.

B. allosteric site.

RQ 2: The cell wall of Gram-positive bacteria would NOT contain: A. peptidoglycan. B. lipopolysaccharides. C. teichoic acids. D. proteins.

B. lipopolysaccharides.

RQ 5: Amylases are enzymes that degrade: A. cellulose B. starch C. glutamate D. lactose

B. starch

RQ 3: The molecule that an enzyme acts upon is known as its: A. apoenzyme. B. substrate. C. coenzyme. D. holoenzyme. E. catalyst.

B. substrate

Assignment 1: What is the name of the enzyme that sulfa drugs target?

B. DHPS

MICROBE OF THE DAY #5 Pyrolobus fumarii

-Archaeal species -from hydrothermal vents in Mid-Atlantic Ridge -90-113degC -chemolithotroph -H2 or S as an energy source Domain: Archaea Phylum: Crenarchaeota Class: Thermoprotei Order: Desulfurococcales Family: Pyrodictiaceae Genus: Pyrolobus Species: fumarii

MICROBE OF THE DAY #4 Geobacter metallireducens

-Gram (-) -metal reducing proteobacterium -strict anaerobe -used for BIOREMEDIATION -used to clean up the Colorado River -respire on acetate

MICROBE OF THE DAY #1 Proteus mirabilis

-Gram (-), rod-shaped, related to e. coli -Causes urinary tract infections -*SWIMMER CELLS TO SWARMER CELLS* Kingdom: Bacteria Phylum: Proteobacteria Class: Gamma Proteobacteria Genus: Proteus Species: mirabilis

MICROBE OF THE DAY #2 Escherichia coli

-Gram(-) -facultative anaerobe -found in the lower intestines of warm-blooded animals -chemoheterotroph: needs carbon and energy sources -model organism Domain: Bacteria Phylum: Proteobacteria Class: Gamma Proteobacteria Order: Enterobacteriales Family: Enterobacteriaceae Genus: Escherichia Species: coli

MICROBE OF THE DAY #3 Thermus aquaticus

-isolated from Hot springs in Yellowstone -gets energy from nearby cyanobacteria -grows b/w 50-80degC (122-176degF) -source of taq DNA polymerase, used in PCR -short rod shape, long filament Domain: Bacteria Phylum: Deinococcus-thermus Class: Deinococci Order: Thermales Family: Thermaceae Genus: Thermus Species: aquaticus

MICROBE OF THE DAY #6 Dehalococcoides

-organohalide respiration -only grows using halogenated compounds as e- acceptors -Able to degrade toxins including PVC, carcinogens, PCBs -used for bioremediation for contaminated groundwater

RQ 4: The TCA cycle produces: A. ATP, FAD, and precursor metabolites B. FADH2, NADH, and precursor metabolites. C. precursor metabolites only D. NADH, ATP, and FAD.

B. FADH2, NADH, and precursor metabolites.

RQ 2: Which of the following bacterial structures plays an important role in the creation of biofilms (a polymer-encased microbial community)? A. Flagella B. Glycocalyx C. Endospores D. Pili E. Teichoic acids

B. Glycocalyx

RQ 5: Why would a cell ferment rather than respire? A. There's no oxygen present, and it cannot respire anaerobically. B. There is no oxygen present and it cannot use anaerobic respiration OR it lacks the ability to respire (i.e., no electron transport chain). C. It lacks the ability to respire (i.e. no electron transport chain). D. More ATP is produced for the cell by fermentation than by aerobic respiration.

B. There is no oxygen present and it cannot use anaerobic respiration OR it lacks the ability to respire (i.e., no electron transport chain)

RQ 6: Which of the following are representative genera of Purple Bacteria? (Select all that apply) A. Chromatium B. Thiospirillum C. Rhodobacter D. Chlorobium

A. Chromatium B. Thiospirillum C. Rhodobacter

RQ 3: Which of the following serve(s) as energy source for a chemolithoautotroph? (Select all that apply) A. H2 B. amino acids C. glucose D. Fe2+

A. H2 and D. Fe2+

RQ 7: Organisms that use organic molecules as their source of carbon are called A. Heterotrophs B. lithotrophs C. Autotrophs D. Phototrophs

A. Heterotrophs

Assignment 2: What was the energy source for the chemosynthetic bacteria living in Riftia? A. Hydrogen sulfide B. Hydrogen gas C. Carbon dioxide D. Far-red light

A. Hydrogen sulfide

RQ 1: Oil immersion is used because it increases: A. Resolution B. Contrast C. Refracted light D. The working distance between the lens and the specimen

A. Resolution

Assignment 1: Which best describes the mechanism of action of sulfa drugs?

A. They compete with the intended substrate (PABA) by binding to the active site of the intended enzyme.

RQ 4: Anaerobic respiration harvests ______ energy than aerobic respiration because of the lower electron affinities of the terminal electron acceptors used: A. less B. more C. the same amount of D. None of the above. In order to properly answer this question, one must know the electron acceptors being used.

A. less

RQ 4: Which cellular process results in the most significant production of ATP? A. oxidative phosphorylation B. Krebs cycle C. glycolysis D. fermentation

A. oxidative phosphorylation

RQ 1: A scientist is using an objective lens of 40x magnification on his microscope. If the ocular lens is 10x, what is the total magnification being used to visualize the specimen? A. 40x B. 400x C. 50x D. 4000x

B. 400x

RQ 7: A colony-forming unit (CFU) is a: A. A tool used to collect clinical specimens B. A single cell or group of related cells that give rise to a colony C. A special type of growth medium D. A commonly used phylogenetic technique

B. A single cell or group of related cells that give rise to a colony

RQ 1: Identify the potential staining method that is most important in the diagnosis of tuberculosis, caused by MICOBACTERIUM TUBERCULOSIS: A. Gram stain B. Acid-fast stain C. Negative staining D. Endospore staining

B. Acid-fast stain

Assignment 2: What is a trophosome? A. The mouth of the tubeworm B. An organ of the tubeworm that houses symbiotic bacteria C. A stinging tentacle attached to the skin of the tubeworm D. An organ of the tubeworm that digests invading bacteria

B. An organ of the tubeworm that houses symbiotic bacteria

RQ 6: If you examined the acidic runoff from a coal mine, which of the following genera would you most likely find growing there? A. Clostridium B. Escherichia C. Acidithiobacillus D. Thermus

C. Acidithiobacillus

RQ 1: If a microbiologist omitted the decolorizer from a gram-stained smear, which of the following would happen? A. Gram positive cells would be pink and gram negative cells would be purple B. All cells in the smear would be pink C. All cells in the smear would be purple D. All cells in the smear would be colorless

C. All cells in the smear would be purple

Assignment 1: Scientists isolated the enzyme targeted by sulfa drugs from which of the following bacterial species (select all that apply):

C. Bacillus anthracis D. Yersinia pestis

RQ 1: Staining is an important way to improve which of the following aspects of microscopy? A. Magnification B. Wavelength of illumination C. Contrast D. Numerical aperture

C. Contrast

RQ 1: The transmission electron microscope (TEM): A. Is used to observe surface details of cells B. Is used to obtain interior views of cells that have been stained with fluorescent dyes C. Is used to observe fine details of internal cell structure D. Is most likely used in a typical microbiology laboratory

C. Is used to observe fine details of internal cell structure

RQ 2: Which of the following organelles is responsible for producing most of the ATP in a eukaryotic cell? A. Smooth endoplasmic reticulum B. Nucleus C. Mitochondrion D. Golgi body E. Lysosome

C. Mitochondrion

RQ 5: Beta-oxidation is: A. The removal of oxygen from the second (or beta) carbon of glucose during glycolysis. B. The second oxidation step in fermentation that results in the production of ethanol and other fermentation products. C. The process utilized for the catabolism of fatty acids. D. A byproduct of the light-independent reaction that interferes with carbon fixation.

C. The process utilized for the catabolism of fatty acids.

Assignment 1: Which phrase best describes the interaction of PABA and its enzyme?

C. Two floppy loops wrap around PABA and hold it in place.

RQ 7: Which of the following techniques would best determine the number of living cells in a culture? A. Coulter counter B. Most Probable Number C. Viable plate count D. Direct microscope count

C. Viable plate count

RQ 7: A microorganism isolated from the Arctic region would most likely be: A. a mesophile B. Facultative C. a psychrophile D. a thermophile E. a halophile

C. a psychrophile

RQ 2: endospores: A. are reproductive structures of some bacteria. B. occur in some Archaea C. are dormant, heat resistant forms of some bacteria. D. can cause fever, shock and inflammation.

C. are dormant, heat resistant forms of some bacteria.

RQ 2: Bacterial Flagella: A. are enclosed in a membrane similar to those of eukaryotic flagella. B. are used for attachment. C. are used for motility. D. have the same structural composition as eukaryotic flagella

C. are used for motility.

RQ 4: In prokaryotes, where do the central metabolic pathways occur? A. mitochondria B. peptidoglycan C. cytoplasm D. chloroplasts

C. cytoplasm

RQ 6: Thermoplasma and Picrophilus grow best in which of the following extreme conditions? A. low pH B. high salt C. low pH and high temperature D. high pH and high temperature

C. low pH and high temperature

RQ 3: Which of the following are factors that influence an enzyme's activity? A. pH B. temperature C. salt D. inhibitors E. All of the above.

E. All of the above

RQ 2: Plasmids are: A. associated with the ribosomes of bacteria. B. are associated with nuclear histones C. often transferable between bacteria, accounting for the spread of antibiotic resistance. D. extrachromosomal DNA molecules in bacteria that encode essential genetic information.

C. often transferable between bacteria, accounting for the spread of antibiotic resistance.

RQ 3: All of the following are forms of oxidation EXCEPT: A. loss of a hydrogen atom. B. gain of an oxygen atom and its electrons. C. substrate level phosphorylation. D. loss of an electron.

C. substrate level phosphorylation.

RQ 5: Fermentation: A. uses an inorganic molecule as the final electron acceptor. B. results in the production of a large amount of ATP. C. uses an organic molecule as the final electron acceptor. D. is necessary in some organisms to produce reduced electron carriers.

C. uses an organic molecule as the final electron acceptor.

Assignment 2: What surprised the researchers on Alvin when they arrived at the hydrothermal vents? A. Hot water temperatures B. Volcanic activity C. Low light levels D. An abundance of life

D. An abundance of life

Assignment 2: The trophosome of Riftia pachyptila was found to be full of sulfur crystals. Why were there sulfur crystals in the trophosome? A. The trophosome filters toxic sulfides from the water and converts it to sulfur crystals, which are less toxic. B. The trophosome absorbs sulfides in order to digest it for energy. C. Giant tube worms produce and store sulfur crystals because predators don't like the taste of them. D. Bacteria in the trophosome use sulfides as an energy source for making organic compounds, and sulfur is a byproduct of the bacterial metabolism.

D. Bacteria in the trophosome use sulfides as an energy source for making organic compounds, and sulfur is a byproduct of the bacterial metabolism.

RQ 2: The cytoplasmic membranes of all prokaryotic and eukaryotic cells contain ________________. A. Phospholipids. B. Nucleic Acids. C. Proteins. D. Both phospholipids and proteins.

D. Both phospholipids and proteins.

RQ 6: If you read that coliforms had been found in a lake, the report could have been referring to which of the following genera? A. Bacteroides B. Bifidobacterium C. Clostridium D. Escherichia

D. Escherichia

RQ 7: Microbial growth is at its maximum rate during which of the following phases of the growth curve? A. Stationary Phase B. Lag Phase C. Death Phase D. Exponential Phase

D. Exponential Phase

Assignment 1: What pathway do sulfa drugs affect?

D. Folate synthesis

Assignment 2: Researchers on the first Alvin dive in 1977 were looking for: A. New habitats for humans to colonize B. Minerals that could be mined C. Deep sea ridges D. Hydrothermal vents

D. Hydrothermal vents

RQ 7: In a defined medium: A. organic molecules are always excluded b. Agagr is available for microbial nutrition C. Blood may be included D. The exact chemical composition is known

D. The exact chemical composition is known

RQ 3: Which of the following is not an electron carrier? A. NADP+ B. FAD C. NAD+ D. Trace elements

D. Trace elements

RQ 4: The transition step: A. links glycolysis to the pentose phosphate pathway B. takes place in the matrix of the nucleus. C. None of the above. D. links glycolysis to the TCA cycle. E. links the pentose phosphate pathway to the electron transport chain.

D. links glycolysis to the TCA cycle.

RQ 3: Which molecule serves as the terminal electron acceptor in aerobic respiration? A. NAD+ B. nitrogen C. glucose D. oxygen E. FAD

D. oxygen

RQ 7: A medium that inhibits the growth of organisms other than the one being sought is called a(n) A. differential medium B. synthetic medium C. enrichment medium D. selective medium

D. selective medium

RQ 1: Put the following steps of specimen preparation and staining in order: I. Application of staining Dyes II. Heat fixation III. Smear preparation

III, II, I

RQ 1: To observe a bacterial cell under the light microscope, the _________ dye is used, which takes advantage of the negative charges associated with cellular components:

Positively charged, or Basic

RQ 2: Penicillin and lysozyme are more effective against Gram-positive bacteria than Gram-negative bacteria: True False

True

RQ 6: Hydrogen sulfide serves as an energy source for chemolithotrophs: True False

True