Micro Exam #1 Questions

Penicillin interferes with cell wall synthesis. Which of the following cells is most likely to be damaged by penicillin? A. Human cells B. Yeast cells C. Cells of archaea D. Gram-positive bacterial cells

Gram-positive bacterial cells

The deep water Horizon oil spill in the gulf of Mexico resulted in an explosion of microbial growth and metabolic activity in the water column. Which of the following statements would be true: A. The oil provided an abundant source of carbon B. The organisms stimulated to grow would be halophiles C. The organisms on the cold sea floor stimulated to grow might be psychrophiles D. Hmmm, all these statements are true...

Hmmm, all these statements are true...

Regarding the viral membrane of an enveloped virus, the lipids are derived from the ___, and the proteins are encoded by ___. A. Host's cell membrane/ viral genes B. Virion/ viral genes C. Host's cell membrane/ host's genes D. Virion/ host's genes

Host's cell membrane/ viral genes

Two major types of symmetry found in viruses include a. Icosahedral and radial b. Icosahedral and helical c. Helical and radial d. Radial and bilateral

Icosahedral and helical

Antibiotic drugs that are bacteriostatic A. Kill bacteria B. Promote bacterial growth C. Inactivate bacterial spores D. Inhibit the growth of bacteria

Inhibit the growth of bacteria

Viral replication occurs only a. Intracellularly b. Extracellularly c. Both intracellularly and extracellularly d. Either intracellularly or extracellularly, depending on the virus involved

Intracellularly

All of the following statements are true about antibiotic resistance EXCEPT: a. It can develop a course of antibiotic treatment b. It has become a serious problem in the United States c. It can be reversed by discontinuing the use of certain antibiotics for a few years d. It is a result of misuse and overuse of antibiotics

It can be reversed by discontinuing the use of certain antibiotics for a few years

Who of the following developed a set of criteria that could be used to establish a causative link between a particular microorganism and a particular disease? a. Fracastoro b. Koch c. Pastuer d. Lister

Koch

Which of the following is not a characteristic of certain psychrophilic bacteria that enables them to survive and grow at low temperatures A. More hydrogen bonds B. More proline C. Less saturated and les branched lipids on the cell plasma membrane D. Histone-like proteins stabilize DNA

Less saturated and less branched lipids on the cell plasma membrane

The theory of spontaneous generation was refuted by the work of a. Louis Pasteur b. Robert Koch c. Robert Hooke d. Antoni van Leeuwenhoek

Louis Pasteur

The domains of life in current biological classification schemes include a. Bacteria, Archaea, and Viruses b. Eukarya, Prokaryotes, and Viruses c. Viruses, Eukaryotes, and Prokaryotes d. None of the above

None of the above

In an enveloped virus, the part of the virus including the nucleic acid genome and the surrounding protein coat but not the envelope is called the a. Capsid b. Nucleocapsid c. Matrix d. Virion

Nucleocapsid

Which of the following does not inhibit protein synthesis? a. Tetracycline b. Streptomycin c. Erythromycin d. Penicillin e. All of the choices inhibit protein synthesis

Penicillin

Prions are ___, and affect the ___ A. Nucleic acids; respiratory system B. Lipids; gastrointestinal tract C. Peptides; nervous system D. Saccharide; lymphatic system

Peptides; nervous system

Which of the following protects bacteria from lysis in dilute solutions and helps to determine their cellular morphology or shape? a. Plasma membrane b. Peptidoglycan c. Capsule d. Gas vacuoles

Peptidoglycan

Which of the following pairs is mismatched? A. Lysosome; digestive enzymes B. Ribosomes; storage C. Golgi complex; secretion D. Mitochondria; ATP production E. Endoplasmic reticulum; internal transport

Ribosomes; storage

Bacteria synthesize low-weight molecules called ___ to scavenge iron from their environment, which strongly bind extracellular ferric iron and are recognized by membrane receptors and transported into the bacterial cytoplasm. A. Phosphoenolpyruvate B. ATP-binding cassette C. Siderophores D. Phosphotransferase E. Heme

Siderophores

The evolutional ruler for prokaryotic taxonomy identification and phylogenetic analysis is? A. Small subunit RNA genes B. 18S rRNA genes C. 16S rRNA D. 70S rRNA genes

Small subunit RNA genes

Which organism could be found living in a Yellowstone hotspring? A. Thermophile B. Mesophile C. Metaphile D. Psychrophile

Thermophile

Who of the following as the first to observe and accurately describe microorganisms? A. Pasteur B. Lister C. Van Leeuwenhoek D. Tyndall

Van Leeuwenhoek

During period of cell starvation ____. A. Cross-linking in cell wall increases B. Morphology of cells changes C. Protoplasts shrinks, and nucleoid condenses D. Cells are called persister cells with endospore formation E. All changes above are true

All changes above are true

A set of experiments that might be usd to decide if a particular microbe is the causative agent of a disease A. The pathogen bacterium should be isolated and grown in culture B. The germ must be show on the patient C. The disease is sure to be caused by the pathogen germ D. The species should be isolated from the patient E. All the above

All of the above

The Archaea generally lack which of the following that are normally found in gram-negative bacteria? a. Outer membrane (not the inner cytoplasmic cell membrane). b. A complex peptidoglycan network c. Lipopolysaccharide d. All of the above

All of the above

Quorum sensing a. Is a phenomenon in which bacteria monitor their own population density b. Depends on the sensing of signal protein molecules c. Plays an important role in formation of biofilms by Pseudomonas aeruginosa d. All of the choices

All of the choices

Which of the following can be used to isolate pure cultures of bacteria from mixtures? a. Spread plates b. Streak plates c. Pour plates d. All of the choices

All of the choices

Which of the following is a desirable general characteristic of antimicrobial drugs? A. Selective toxicity B. Broad-spectrum of activity C. Bactericidal rather than bacteriostatic D. All of the choices

All of the choices

Which of the following eukaryotic cells do NOT contain a cell wall A. Animals B. Plants C. Algae D. Fungi

Animals

ALL viral particles a. Are metabolically inert while living outside of host cells b. Are likely equal to the size of bacterial cells c. Always contain an envelope to prevent its degradation outside of a host d. Infect only animals and plants

Are metabolically inert while living outside of host cells

Who is usually creited with the discovery of penicillin? a. Fleming b. Florey and Chain c. Ehrlich d. Koch

Fleming

The time interval required for the formation of two cell from on is called the a. Generation time b. Growth time c. Growth rate d. Division rate

Generation time

Bacterial and archaeal ribosomes are known to have the size of ___, based on their sedimentation coefficient? a. 50S b. 30S c. 80S d. 70S

70S

Active transport of solutes in bacteria involves in A. ATP or proton motive force B. Carrier proteins C. The moving of the chemicals from high to low concentrations D. A and B

A and B

A clear zone of phage infection in a bacterial lawn is A. A prophage B. A plaque C. Naked D. A capsomere

A plaque

The E test is a. A rapid serological test used to detect the presence of eastern equine encephalitis virus in cerebrospinal fluid b. A quantitative antibiotic sensitivity test that utilizes plastic strips impregnated with an antibiotic of interest c. Used to quantify levels of IgE antibody in serum samples d. Used to measure esculine levels in pasteurized milk

A quantitative antibiotic sensitivity test that utilizes plastic strips impregnated with an antibiotic of interest

Bacillus anthracis causes the deadly disease anthrax. Organisms of the genus Bacillus may form endospores. This bacterium would be suitable for biological warfare because endospores ____. A. Have a high concentration of calcium ions B. Are difficult to stain C. Are resistant to high temperatures, UV light, and desiccation D. Are multilayered structures E. Are centrally located within the bacterial cells

Are resistant to high temperatures, UV light, and desiccation

The most selective antibacterial agents are those that interfere with bacterial cell wall synthesis. This is because A. Bacterial cell walls have a unique structure not found in eukaryotic host cells B. Bacterial cell wall synthesis is easily inhibited whereas eukaryotic cell wall synthesis is more resistant to the actions of the drug. C. Eukaryotic cells do not take up the drugs D. Eukaryotic cells inactivate the drugs before the can do any damage

Bacterial cell walls have a unique structure not found in eukaryotic host cells

The use of the Gram stain in microbiology is important because it differentiates a. Bacteria from Archaea b. Prokaryotic from eukaryotic cells c. Bacterial cells with different types of cell walls d. Archaeal ells with different types of metabolism

Bacterial cells with different types of cell walls

The use of enrichment cultures and selective media was pioneered by? a. Jenner b. Beijerinck c. Pasteur d. Von Behring

Beijerinck

Definition of life includes all of the following Except a. Cells maintain internal order b. Cells use energy and have a metabolism c. Cells reproduce d. Cells lack response to external environment

Cells lack response to external environment

Peptidoglycan A. Consists of lipids and proteins B. Regulates entry and exit of the cell via transport proteins C. Consists of repeating units of N-acetyl glucosamine and N-acetyl muramic acid D. Is found only in gram positive bacteria

Consists of repeating units of N-acetyl glucosamine and N-acetyl muramic acid

The nuclear area of the bacterial cell ____ A. Has abundant histone proteins B. Is connected to the endoplasmic reticulum C. Is enclosed in a nuclear membrane D. Contains the bacterial chromosome

Contains the bacterial chromosome

The correct experimental procedures to identify bacterial isolate species and analyze its phylogenetic relationships are listed below

Correct answer: Cell cultures-DNA extraction-amplification of 16S rRNA genes-sequence alignment and blasting-phylogenetic analysis

Prions are of significance because they cause infections of a. Domestic animals and humans b. Plants c. Fungi d. Prokaryotes

Domestic animals and humans

Which of the following membrane transport mechanisms takes place in eukaryotic cells but NOT in prokaryotic cells? A. Endocytosis B. Active transport C. Facilitated diffusion D. Osmosis

Endocytosis

Sampling lake water for microscopic organisms is no as easy as it sounds when you want to both count and identify species. In a given water sample, your bacteria of choice can be rare or difficult to culture, particularly given the mixture of bacteria in a biofilm. Which of the following culture media would e best for growing fecal coliforms (e.g. E. coli) when they are relatively less abundant than other bacteria in the lake? A. Complex culture medium B. Basic culture medium C. Anaerobic culture medium D. Enrichment culture medium

Enrichment culture medium

Mg, Zn, and Fe are macronutrients A. TRUE B. FALSE

FALSE

The 70S prokaryotic ribosome consists of a small and large subunit which contains RNA, protein, and DNA A. TRUE B. FALSE

FALSE

Which of the following processes uses membrane proteins that act as channels or carriers allowing ions or large molecules to move across the plasma membrane without using energy? a. Active transport b. Simple diffusion c. Facilitated diffusion d. Osmosis

Facilitated diffusion

Glycoprotein spikes protruding from the outer surface of viral envelopes function as a. Toxins b. Factors that bind to host cells c. Cell lysis factors d. Factors needed for site specific recombination

Factors that bind to host cells

The minimal lethal concentration (MLC) is the a. Lowest concentration of a drug that prevents growth of a particular pathogen b. Highest concentration of a drug that prevents growth of a particular pathogen c. Lowest concentration of a drug that kills a particular pathogen d. Highest concentration of a drug that kills a particular pathogen

Lowest concentration of a drug that kills a particular pathogen

A phage that replicates inside the host cell and then lyse its host during its release is a A. Lytic phage B. Latent phage C. Lysogenic phage D. Filamentous phage

Lytic phage

Bacteria that are able to grow in humans and cause disease have likely evolved to be a. Psychrophiles b. Mesophiles c. Thermophiles d. Hyperthermophiles

Mesophiles

Ribosomes associated with cells or organelles have a certain size, which is expressed in Svedberg units. Which associations are incorrect? A. Chloroplasts- 70S B. Green algal cytoplasm- 80S C. Photosynthetic bacteria-70S D. Mitochondria- 80S

Mitochondria- 80S

The Archaea do not use ____ as a mechanism for reproduction a. Binary fission b. Budding c. Mitosis d. Fragmentation

Mitosis

Which of the following statements about antibiotics is true? A. A chemical that kills gram-positive bacteria and gram-negative bacteria is narrow spectrum B. Most of the antibiotics were originally produced by Streptomyces, a genus of filamentous soil bacteria C. Penicillin was first discovered by two researchers named Florey and Chain D. Antibiotics are not typically produced by microorganisms growing in their natural environment

Most of the antibiotics were originally produced by Streptomyces, a genus of filamentous soil bacteria

All of the following are current methods of counting viruses EXCEPT A. Count viral particles by electron microscope B. Epifluorescence microscopy counting C. Hemagglutination assay D. Most probable number technique E. Plaque assays

Most probable number technique

Chemotaxis refers to the ability of microorganisms to ____. A. Move in a wavelike motion B. Escape phagocytosis C. Move toward or away from chemical stimuli D. Attach to solid surfaces

Move toward or away from chemical stimuli

Shrinkage of the plasma membrane away from the cell wall when the bacterium is placed in a hypertonic environment is called a. Osmolysis b. Plasmolysis c. Hydrolysis d. Hypertonolysis

Plasmolysis

Which of the following microorganisms is an example of a hyperthermophile A. Chlamydomonas nivalis B. Escherichia coli C. Pyrolobus fumarii D. Staphylococcus aureus

Pyrolobus fumarii

The simplest viruses consist of a. RNA only b. Protein only c. RNA or DNA in a protein coat d. RNA and DNA in a protein coat covered with a lipid envelope e. RNA, DNA, and enzymes in a protein coat with a lipid envelope

RNA and DNA in a protein coat covered with a lipid envelope

Viroids are ___, and primarily infect ___ A. DNA; animals B. RNA; plants C. Lipids; bacteria D. Proteins; fungus

RNA; plants

Chemical uptake by the Group Translocation is conducted by several enzymes while the chemical structure itself is phosphorylated A. TRUE B. FALSE

TRUE

Micronutrients mostly are used as enzymes and cofactors. A. TRUE B. FALSE

TRUE

Taq polymerase was isolated from a thermophile and is used in the polymerase chain reaction (PCR) technique because it does not become inactivated at high temperatures a. TRUE b. FALSE

TRUE

The different adaptation of aerobes and anaerobes to oxygen is the presence and absence of protective enzymes including superoxide dismutase (SOD), catalase and peroxidase A. TRUE B. FALSE

TRUE

Which of the following is the correct order for binary fission? A. A septum forms at midcell, the cell elongates, replicates its chromosome, and separates the chromosome into the two parts of the cell B. The cell elongates, a septum forms at midcell, the cell replicates its chromosome, and separates the chromosome into the two parts of the cell C. The cell elongates, replicates its chromosome, and separates the chromosome into the two parts of the cell and a septum forms at midcell D. None of these

The cell elongates, replicates its chromosome, and separates the chromosome into the two parts of the cell and a septum forms at midcell

Lipopolysaccharide (LPS) is associated with ___. A. The outer membrane of Gram positive bacteria B. The outer membrane of Gram negative bacteria C. The cytoplasmic membrane of Gram positive bacteria D. The cytoplasmic membrane of Gram negative bacteria.

The outer membrane of Gram negative bacteria

What statement most accurately describes the structure of the plasma membrane? A. Peripheral proteins span the membrane B. The plasma membrane is a phospholipid bilayer with the hydrophilic phosphate groups oriented toward the inside and outside of the cell C. The lipid portion of the bilayer is hydrophilic D. The plasma membrane s a phospholipid bilayer with the hydrophilic phosphate groups oriented toward one another

The plasma membrane is a phospholipid bilayer with the hydrophilic phosphate groups oriented toward the inside and outside of the cell

The nucleus of a eukaryotic cell differs from the nucleoid of a prokaryotic cell in all of the following ways EXCEPT which one? A. The prokaryotic nucleoid usually contains single circular chromosome, whereas the eukaryotic nucleus contains multiple linear chromosomes B. The eukaryotic nucleus is surrounded by a nuclear envelope. There is no envelope surrounding the prokaryotic nucleoid C. The prokaryotic nucleoid contains DNA combined with histones. Histones are lacking in the eukaryotic nucleus D. The eukaryotic nucleus contains nucleoli. There are no nucleoli in the prokaryotic nucleoid.

The prokaryotic nucleoid contains DNA combined with histones. Histones are lacking in the eukaryotic nucleus

Deduce why viruses are excluded from the ribosomal RNA-based tree of life. a. Some viruses contain multiple strands of RNA b. Their genetic elements cannot be sequenced c. They can infect other organisms, which complicates the genetic comparisons d. They lack ribosomal RNA

They lack ribosomal RNA

The features of Gram-positive bacteria different from Gram-negative bacteria include A. Thinner peptidoglycan layer, less periplasmic space, and simpler outer membrane B. Thick peptidoglycan layer, larger periplasmic space, and complex outer membrane C. Thick peptidoglycan layer, less periplasmic space, and simpler outer membrane D. Thinner peptidoglycan layer, larger periplasmic space, and complex outer membrane

Thick peptidoglycan layer, less periplasmic space, and simpler outer membrane

The gram stain divides microorganisms into two groups, purple vs. red, on the basis of differences in the A. Presence of a capsule B. Presence of an outer membrane C. Thickness of the peptidoglycan layer of the cell wall D. Presence of waxy mycolic acids in the cell wall E. Presence of endospores

Thickness of the peptidoglycan layer of the cell wall

Mitochondria and chloroplasts were originally evolved from bacteria. a. True b. False

True

Whose discovery of streptomycin stimulated an intense search for other antibiotics? a. Waksman b. Pasteur c. Ehrlich d. Fleming

Waksman

The ribosomal RNA studies that led to the division of prokaryotic organisms into the Bacteria and the Archaea were begun by: a. Pasteur b. Woese c. Needham d. Watson

Woese