What is the major difference between disinfectants and antibiotics?
C. Antibiotics are more specific for killing bacteria than disinfectants
_____________ theory, proposed by ________, states that mitochondria and chloroplasts evolved from bacteria.
E. Endosymbiotic, Margulis
As accepted in modern biology, _____ domains of life are __________
D. Three; Bacteria, Archaea, and Eukarya
Find one statement that is NOT correct regarding Koch’s postulates.
A. The pathogen must be shown to contain toxins.
________ limits what we can see with a microscope and if apparent size of an object is increased without increasing details, it is called ____________
e. Magnification; empty resolution
C. Resolution, empty magnification
What is the total magnification of a light microscope when using a 25X ocular and 40X objective lens?
A. 1000X
Which of the following would NOT be suited to observe live cells?
D. Scanning Electron Microscopy
A fluorophore used in fluorescence microscopy that absorbs light at 300 nm would most likely fluoresce at:
C. 400 nm
Which of the following statements is/are TRUE?
C. Bacilli are rod shaped bacteria
All of the following are used to lyse cells EXCEPT
B. ultracentrifugation
All of the following statements regarding phospholipids of the cell membrane are true EXCEPT:
A. They make the membrane fluid.
Which of the following statement is FALSE regarding Gram positive bacteria?
D. Outer membrane of all Gram + bacteria has LPS
Directed movements toward or away from a chemical or physical signal are known as:
A. chemotaxis
Marine viruses play a significant role in ecology because ____________
D. All above statements are correct
Which of the following proteins represents a coupled transport system where two molecules travel in the opposite direction?
A. antiport
All of the following statements about DNA are true EXCEPT:
B. DNA is organized in nucleus in prokaryotes
Growth of MOST microorganisms occurs by:
C. binary fission
The bacteria Vibrio owensii has a generation time of 8 minutes. Starting with two cells in log phase, how many minutes does it take to produce 256 cells? Assume all cells remain viable.
B. 56
Prions are _______ agents that infect _______.
D. protein; animals
What is NOT a macronutrient?
C. zinc
__________ REQUIRE very low temperatures and high pressure for growth.
C. Barophilic psychrophiles
All of the following statements regarding eukaryotes are false EXCEPT:
D. Organelles provide increased membrane surface per total cell volume
__________ medium is one of higher osmolarity than the cell.
B. hypertonic
______________ helps solutes move across a membrane from high to low concentration
A. Facilitated diffusion
A bacterium that thrives in your stomach is probably a(n):
C. acidophile
Which best describes facultative anaerobes?
B. They will use oxygen if it is present, but can grow even if oxygen is not present.
A virus that infects bacteria is called a:
d. bacteriovirus
e. bactericide
A. bacteriophage
Choose correct statement(s) about biofilms.
A. Biofilms are composed of one or more different species of microorganisms
Some viral species may derive their __________ from host membrane.
A. envelope
Human pathogens are mostly:
C. mesophiles
In lysogenic cycle a virus _________
D. Both statements a. and c. are correct
In contrast to animal viruses, plant viruses infect cells by mechanisms that do NOT involve specific:
C. receptors
The Baltimore system classifies viruses based predominantly on
A. their means of mRNA synthesis
What do ALL viruses contain?
A. capsid and genome
Which statement is NOT correct
C. LPS is located in the inner membrane of Gram - bacteria
Which of the following molecules can be easily transported by passive diffusion through membrane without any aid of transporters?
D. CO2
The __________ is the region between the cytoplasmic membrane and the outer membrane in Gram-negative cells.
D. periplasm
Lithotrophs are organisms that feed on _______, and were discovered by _______.
D. inorganic material; Sergei Winogradski
What does analysis of 16S rRNA sequences show?
D. Archaea are as distant from bacteria as from eukaryotes.
All microorganisms have genomic DNA, except:
e. none of them are correct
D. some viruses
Which of the following is NOT true about the two strands of DNA in a double helix?
C. They must have equal amounts of thymine and cytosine.
Supercoiling in bacteria is typically introduced by an enzyme called:
e. ligase
C. topoisomerase
All following statements about DNA and RNA are true, except:
C. RNA has the same bases as DNA
Find correct statement(s) about genomes.
B. Archaea have circular genomes like bacteria
Gene transfer from parent to child is called:
B. vertical transmission
Plasmids can replicate by:
D. either b or c
__________________ replication of DNA means that each daughter cell receives one parental and one newly
synthesized strand
A. Semiconservative
Identify a protein that is NOT involved in DNA replication process
C. Permease
The leading strand is synthesized __________ , while the lagging strand is synthesized __________.
E. continuously; discontinuously
A primer is a short ____________ sequence complimentary to the template that allows DNA polymerase to start polymerization by attaching the first nucleotide to the primer’s _________ end during DNA replication.
A. RNA; 3’
Nucleotides in DNA are covalently joined by__________
C. phosphodiester bonds
Ames test is used to screen compounds for:
C. mutagenicity
__________ RNA polymerase plus sigma factor together are called __________.
B. Core; holoenzyme
All statements about sigma factor are correct, EXCEPT:
B. Sigma factors are bound to RNA polymerase during all steps of transcription
What does it mean to say that the genetic code is redundant?
A. More than one codon can specify the same amino acid.
Find incorrect statement about transcription and translation.
A. Translation is reading a DNA template to make an RNA copy
__________ is a process that involves cell-to-cell contact to move the plasmid from a donor cell to a recipient cell.
D. Conjugation
__________ cut a foreign DNA at specific sites for protection from invading viruses.
B. Restriction endonucleases
Which form of RNA has the task of unsticking stuck ribosomes?
D. tmRNA
What gene transfer process would be sensitive to extracellular nucleases?
e. transduction
B. transformation
Bases of two opposite DNA strands are forming _______ to “recognize” each other.
E. hydrogen bonds
After extensive DNA damage, special DNA polymerases are expressed that sacrifice replication __________ to rescue the damaged genome.
E. accuracy
Transcriptional attenuation is a common regulatory strategy used to control many operons that code for what?
E. amino acid biosynthesis
A quorum-sensing gene system requires the accumulation of a secreted small molecule called a(n):
C. autoinducer
A protein of interest can be specifically detected on western blots; this technique requires:
D. all of the above
There is only ONE correct statement bellow regarding translation. Find it!
C. RNA, not protein, is responsible for peptidyltransferase activity
What kind of gene expression controls are revealed by gene fusions?
C. both transcriptional and translational
What kind of gene expression controls are revealed by gene fusions?
a. transcriptional
b. translational
c. both transcriptional and translational
d. posttranslational
e. none of the above
What kind of gene expression controls are revealed by operon fusions?
A. transcriptional
The electrophoretic mobility shift assay (EMSA) is utilized to monitor molecular interactions between:
C. DNA and protein
RNA fragments can be separated on a gel and then detected using a DNA probe by a technique known as:
A. northern blot
The process of importing free DNA into cells is known as:
C. transformation
There is a nonsense mutation in lacZ gene (part of the lacZYA operon). Choose correct statement describing whether or not protein products of these three genes (LacZ, LacY, and LacA) will be made/translated.
C. LacZ will be shorter and LacY and LacA will be made
Homologs that are present in different species, but have the same functions are called:
A. orthologs
All following statements about protein degradation and secretion are true, EXCEPT:
B. Type I secretion system moves proteins from the cytoplasm to the periplasm
Large regions of sequence homology are required when recombining DNA molecules by __________ recombination.
D. general
A loss-of-function mutation could NOT be caused by:
E. silent mutation
Spontaneous mutations can be caused by:
C. tautomers having altered base pairings
Which of the following is NOT true of a pyrimidine dimer?
C. The pyrimidines are base-paired one to another.
Which of the following forms of DNA repair is error-prone?
d. nucleotide
e. photoreactivation excision
B. NHEJ
In some, but not all, instances, ________ molecules bind RNA transcripts and help degradation
C. asRNA
All of the following typically occur in the presence of high glucose and high lactose concentrations EXCEPT:
D. Transcription initiation of the lac operon is enhanced
Complete pyruvate oxidation via TCA cycle produces:
D. all of the above
Which of the following statements is NOT true regarding Krebs cycle?
E. All of the above are true.
Find TRUE sentence(s) about reduction potential (E) below.
E. a and c are true
What molecule has the highest reduction potential from the list below?
E. O2
All statements below are INCORRECT except:
E. Electron transfer is done by metal ions or conjugated double bonds in cofactors
Find incorrect statement below. The proton motive force _________
D. is generated when protons are pumped by ETS into the cell
Which of the following best describes methanotrophy?
B. CH4 is oxidized to CO2
Which of the following best describes methanogenesis?
E. CO2 is reduced to CH4
Which of the following is NOT a redox pair?
B. H2O/H3O+
The laws of thermodynamics indicate that systems tend to become less ordered and that __________, a measure of disorder or randomness of the universe, always ___________.
E. entropy, increases
Enzymes speed up reactions by
D. lowering the activation energy
Find incorrect statement regarding ATP below.
D. ATP is the main energy donor for protein synthesis.
NAD+ is _______ form and NADH is ______ form of this energy carriers, which means that NAD+ can _______ electrons and NADH can __________ electrons.
B. oxidized, reduced, accept, donate
Which of the following statements is NOT true regarding the electron donors in prokaryotic metabolism?
E. All of the above are true.
Which metabolic pathway produces both NADPH and NADH?
A. ED pathway
Fermentation can be defined as ______breakdown of organic food _______the use of an electron transport
system.
A. partial, without
Terminal electron acceptors in anaerobic respiration include all of the following EXCEPT
A. H2S
Cyanobacteria are believed to generate the majority of oxygen gas in Earth’s atmosphere. What allows them to produce oxygen?
B. photosynthesis in which H2O is the electron source
Which is the most stable form of nitrogen and requires a lot of energy to be reduced?
E. N2
The reduction of Fe3+ to Fe2+ by iron reducers during anaerobic respiration is an example of:
C. dissimilatory metal reduction
Which of the following is/are common component(s) of photolytic electron transport systems?
E. all of the above
Microbial biosynthetic processes require:
D. all of the above
The Calvin cycle_________
B. is the reductive pentose phosphate cycle
The level of nitrogen fixation is highest under which of the following conditions?
A. Low levels of O2 and low levels of NH4+
The level of nitrogen fixation is lowest under which of the following conditions?
A. High levels of O2 and high levels of NH4+
In many bacteria, the electron carrier __________ is used for biosynthesis, whereas __________ feeds the electron transport system.
A. NADPH; NADH
Find correct statement(s)!
A. All are correct
Alkaline fermentations raise pH through the catabolism of:
C. Proteins
Leavening of commercial bread dough is brought about by CO2 from:
a. homolactic fermentation
b. aerobic metabolism of yeast
c. alkaline fermentation
d. acidic fermentation
e. ethanolic fermentation
e. ethanolic fermentation
Which of the following conditions limits abiotic oxidation of fats in food (i.e., rancidity)?
E. low oxygen levels
Which of the following conditions limits abiotic oxidation of fats in food (i.e., rancidity)?
E. low oxygen levels
Food fermentation________
D. All of the above statements are correct
Find incorrect statement.
E. All of the above statements are correct
Electron transport systems are embedded in what membrane system, among others?
D. all of the above
The term __________ group indicates that the members of a clade share a common ancestor.
A. monophyletic
What is denitrification?
A. conversion of nitrate or nitrite to N2 by anaerobic respirers
What is nitrification?
B. oxidation of NH4+ to nitrate or nitrite by lithotrophs
The sum total of all DNA sequenced from an environmental sample such as soil sample is called:
E. metagenome
The relationship among endosymbiotic microbes in the termite gut that results in complex metabolic fluxes
with a negative ΔG, and that would NOT happen for individual members, is called:
A. syntrophy
Mycobacterium tuberculosis and human relationship would best be described as:
B. parasitism
A molecular clock is best defined as:
E. the information contained in DNA or protein sequences that shows changes over time
The ancestral organism that gave rise to the modern-day chloroplast was:
D. a cyanobacterium
Lakes that have low concentrations of organic nutrients are termed:
D. oligotrophic
All of the following are thought to have been present in early cell metabolism before expansion of cyanobacteria EXCEPT
B. Aerobic respiration
The laws of thermodynamics indicate that systems tend to become less ordered and that __________, a measure of disorder or randomness of the universe, always increases.
A. Entropy
In most environments, the nutrient concentrations outside the cell are lower than inside the cell. How can a microbial cell obtain nutrients if the concentration gradient is NOT favorable?
A. Through active, energy-dependent transport
Production of traditionally fermented foods typically relies on ______ flora, whereas commercial fermentation generally relies on ________.
D. Indigenous; starter cultures
Which of the following does NOT aid in the retardation of microbial growth?
D. Warming the food to body temperature
The sum of all of Earth’s life is called:
D. Biosphere
Based on small subunit rRNA phylogeny studies, the current view is that there are ____ domains of life
B. 3
Horizontal gene transfer can occur by all EXCEPT for which of the following?
D. Parent to offspring
Mycobacterium tuberculosis bacterium and H1N1 viruses could both be placed in the same category in some medical classification systems based on the fact that they both:
A. Cause lung infection
The release of CO2 by human industry has/is ________ the rate of CO2 fixation globally
C. Outpaced
In marine sediments, CO2 is reduced to CH4 by:
Bacteria containing a. proteorhodopsin
b. Oxygenic Cyanobacteria
c. Methanotrophic archaea
d. Methogenic archaea
e. None of the above
d. Methogenic archaea
Which of the following statements is NOT correct?
B. Fungi are prokaryotes
Microbial life appeared on Earth as early as:
A. 3.8 billion years ago
Eukaryotic organelle structures that are thought to have arisen from endosynthetic relationships include:
E. Mitochondria and chloroplasts
Where do lymphocytes mature?
D. both b and c
Where do lymphocytes encounter antigens?
B. secondary organs
Which cells produce antibodies?
B. B cells
Which cells modulate immune response?
C. T cells
Which of the following is NOT a innate host defenses?