Microbiology unit 2 Flashcards

What is the function of the cyanobacterial antenna complex?

Sulfur oxidation causes environmental__________.

Cyanobacteria are the only prokaryotic phototrophs that___________.

For what purpose do anoxygenic phototrophs with photosystem II (PSII) reaction centers run reverse electron transport?

Hydrogenotrophs use H₂ in what way?

Methanogenesis, NOT methylotrophy, is the __________.

Define Methylotrophy.

Define Methanotrophy.

Nitrifiers obtain energy from which of the following?

Anoxygenic phototrophic bacteria belonging to the genus Chlorobium would likely exist in close proximity to microbes that require sulfate for which of the following?

ATP production in halophilic archaea that contain bacteriorhodopsin differs from ATP production in cyanobacteria in that ONLY cyanobacteria____________.

Photosystem proteins (regardless of the organism in which they are found) share a common ancestry with components of what other biological system?

An organism contains photosystem II but not photosystem I. From this, it can be concluded that the organism__________.

Photoheterotrophic organisms can_______________.

Methylotrophy would refer to microbial oxidation of which of the following for growth?

Define Hydrogenotrophy.

The ability to obtain energy via the oxidation of reduced sulfur compounds (e.g., H₂S) is widespread among prokaryotes (both Bacteria and Archaea). Unfortunately, the nature of the major reaction end product has what effect on the immediate environment?

Is it possible to produce a proton motive force without an electron transport system?

Metabolism using an electron transport system is classified based on the nature of the initial electron donors and terminal electron acceptors. Lithotrophy uses __________ molecules as the __________ electron __________.

What is the terminal electron acceptor in oxygenic photosynthesis?

For every 2 molecules of water consumed, the light reactions of oxygenic photosynthesis generate_______molecule(s) of ATP,_______ molecule(s) of NADPH, and _______ molecule(s) of O₂.

In photoautotrophs, the chemical energy produced by the "light" reactions (i.e., photolysis and electron transport) is used to fuel which cellular process?

In photoautotrophs, the chemical energy produced by the "light" reactions (i.e., photolysis and electron transport) is used to fuel which cellular process?

Which of the following groups is responsible for the vast majority of primary production on the planet?

List substrates of lithotrophy.

List substrates of Organotrophy

Suppose you have isolated a compound that alters the quorum signal of Pseudomonas aeruginosa, such that it cannot interact with its normal receptor. Bacterial cells targeted by such a disrupter would most likely___________.

Pseudomonas aeruginosa represents a well-studied model organism for single-species biofilm formation. This research is also of direct medical significance because of the propensity of these bacteria to form biofilms in the______of patients with cystic fibrosis.

What early events in biofilm formation by Pseudomonas aeruginosa involves the extension and retraction of a specific pilus?

Many biofilm-specific phenotypes are controlled by “quorum sensing.” This system allows bacteria to regulate gene expression according to the concentration of_______in its immediate environment.

Biofilms form_____________.

Why are elements such as cobalt, copper, manganese, molybdenum, nickel, and zinc referred to as micronutrients?

Many bacteria cannot easily be cultured from their natural habitat. Usually that is because those cells normally obtain a necessary metabolite from a host organism (or other member of the microbial community) and can no longer synthesize that requirement for themselves. Examples of such growth factors include all of the following except___________.

Because of its requirement for active transport (ABC transporters) and basic energy transformations, a cell must have some way to generate its own__________.

An essential nutrient is one that__________.

All organisms require_______as a macronutrient.

You have isolated a mutant strain of Bacillus subtilis (which you designate wimP) whose endospores can be killed by boiling water. When you analyze the endospores produced by this strain, you find that compared to endospores produced by the parent (a wild-type strain), the wimP spores have significantly__________.

Suppose the researcher who ran this experiment also measured growth of the culture by taking optical density readings using a spectrophotometer. During which phase would the data be least proportional to that in the above graph (obtained using numbers of viable cells)?

Cellular synthesis of___________would be directly affected by nitrogen limitation?

Organisms that need to ingest reduced carbon are called__________.

Paenibacillus wynnii uses the oxygen produced by cyanobacteria for which cellular process?

What important role(s) do cyanobacteria play?

Biofilms preferentially form in __________ environments with __________ levels of nutrients.

John Tyndall discovered that intermittent boiling (cycles of heating and cooling) can kill bacterial endospores. This is a result of____________.

Which of the following elements is considered a "macronutrient" even though it is not part of the basic chemical makeup of carbohydrates, lipids, proteins, or nucleic acids?

While adding nutrients to a culture medium in a glass container, which of the following would LEAST likely need to be added and why?

A complex medium is one that___________.

________are resistant to many stresses that would kill vegetative cells.

The first photoautotrophs to evolve did not produce oxygen. What does this most strongly suggest about them?

What capability is shared by many species of Gram-positive pathogens.

What is the role of dipicolinic acid in endospore formation?

Quorum sensing does what?

what equation is used to deal with generations of bacteria and calculating populations of cells?

Biofilms are defined as microbial communities growing within a self-produced extracellular matrix composed primarily of___________.

The number of generations per hour (k)__________

Consider a typical growth curve of a bacterial batch culture grown in the laboratory. Which of the following phases would be shortened, or absent entirely, if the culture was started using an inoculum from a log-phase culture (in the same medium)?

Bacteria as a group are incredibly metabolically diverse, but individual species are often highly specialized to reduce competition in their natural environment. This results in these species being unculturable because____________.

What is the correct order of phases of growth is after a growth of bacteria inoculated into a new culture medium?

For many bacterial types, this component is an absolute requirement for growth, for others it may be toxic, and still for others, some can live with or without it. This component is_______.

The engulfment by the mother cell and deposition of dipicolinic acid highlight this process.

nutrient addition at mid to late log phase allows for further increase in cell yield:

Cellular communication & exopolysaccharide production characterize this.

When severely stressed, these bacteria produce highly resistant dormant forms.

If an inoculum of a particular bacterial species were transferred to a shake flask containing a liquid growth medium lacking an essential nutrient, which growth pattern would likely be observed?

Bacteria capable of thriving in aquatic environments where the external osmolarity is very high would likely be considered________.

_________agents are the same in that both would always yield a decrease in viable count when applied to a susceptible bacterial culture.

Bacteria have higher D-values for irradiation than protists because bacteria have_________.

What is the primary method used by microbes to have water cross the membrane?

Halophiles must have_______NaCl levels to grow.

________kills all cells, spores, and viruses on an object.

_________removes pathogens from inanimate surfaces.

___________removes pathogens from the surface of living tissues.

Oxygen exposure will kill________

Microbes can develop resistance to chemical control agents if_____________.

Chemical disinfectants are intended for_____________.

Barophilic prokaryotes are found primarily_____________.

An organism that grows best at high osmolarity is called____________.

An organism that grows best in cold environments is called____________.

In__________water will flow out of the bacteria by osmosis. This will decrease cell volume.

In__________water will flow into a bacterium by osmosis.

In an_________ the bacterium is at water equilibrium with its environment.

What explains why the death of microbes follows a negative exponential curve?

A steam autoclave attempts to kill bacteria through a combination of____________.

Aerobes may tolerate the presence of oxygen because they have the enzyme____________.

Pasteurization limits microbial numbers through_____________.

Which of the following adaptations is most important in helping microbes be successful in an extreme environment such as a very low pH that would harm normal microbes?

An organism growing in hot sulfur springs is often also_______.

What protein characteristic would be best for psychrophilic microbes?

Which of the following is used as the standard for pasteurization, and why is it used as the standard?

Hydrogen peroxide used as a 6% solution is used to clean wounds on skin as a(n) __________, and it is also used as a stronger solution (>30%) as a(n) __________.

Proteins have optima for___________.

What are the function(s) of the viral capsid.

The viral capsid is comprised of_____________.

Viroids lack________

What are viroids?

What are capsids?

Which viral genome is likely to require an RNA-dependent RNA polymerase for transciption upon viral entry?

Reverse transcriptase catalyzes _____ production from a _____ template.

Control sequences in DNA do not code for proteins, but rather they___________.

The replication of the circular prokaryotic chromosome utilizes two replisomes each of which contains___________.

The replication of the circular prokaryotic chromosome results in_________which must be resolved to form two separate chromosomes.

The lagging strand is synthesized______, and the leading strand is synthesized______.

The replication of the circular prokaryotic chromosome requires the activity of__________.

_____________form the sugar phosphate backbone of DNA.

T/F: The 5’ phosphate at the end of one strand will be directly opposite to the 3’ hydroxyl (‐OH) end of the complimentary
strand.

T/F: One strand of DNA contains purine bases that hydrogen bond to the complimentary strand containing pyrimidine bases.

_____exists as a single strand that may complimentary base pair with itself to form different structures.

T/F: The stability of DNA is much greater than that of RNA.

Plasmids of high copy number are_____likely to be passed on to daughter cells following cell division.

_______typically carry hundreds of genes, usually of multiple metabolic pathways.

The presence of_______is usually not a factor that affects the ability of a cell to maintain a plasmid.

List things required for prokaryotic transcription?

What can cause transcription to end?

What is the importance of the stop codon UAG?

The __________ of transcription and translation helps microbes rapidly adjust gene expression to changes in their
environment.

After __________, each polypeptide must be properly folded and placed at the correct cellular or extracellular location.

T/F: The DNA that comprises prokaryotic genomes has been acquired solely from prior generations.

The presence of competence factors, the formation of translocasomes in the cell membrane, and the presence of extracellular DNA all indicate_________.

An______is capable of transferring a portion of the chromosome during conjugation.

Regarding conjugation an Hfr strain has an______integrated in its chromosome.

Conjugation requires physical contact between cells via the formation of a______.

Bacterium X has acquired an F prime factor from bacterium Y via conjugation. This means that_________.

T/F: In the mechanism of general transduction, only few specific genes from a bacterial chromosome may be passed one from one cell to another via a bacteriophage.

E________can occur between a cell’s chromosome and DNA acquired via conjugation, transduction, or transformation.

Recombination requires_______to scan for homology between the chromosome and acquired DNA.

Recombination results in the formation of_________.

What typically results in an increase in the size of the chromosome?

What can integrate into different regions of the same chromosome or into a different chromosome?

What has a gene that codes for a transposase enzyme that facilitates transfer of the segment.

________may be replicated and the copy integrated elsewhere, or it may excise altogether and “jump” to a new location.

________are flanked by inverted repeat sequences.

Define transposable elements

What is the process that turns off the transcription of a gene or genes?

What uses the Z pathway?

Define photolysis

What are Halobacterium?

What are Bacteriorhodopsin?

Sensory rhodopsin direct the cell toward_____and away from______.

Nitrifiers do what?

Sulfolobus are archaea that oxidize______to______.

Hydrogenotrophy is when__________.

Chlorophylls of plants_____green light while bacteriochlorophylls_____green light with carotenoid pigments.

Light capture maximized by arranging chlorophyll molecules into__________.

A_________is a membrane-bound compartment inside chloroplasts and cyanobacteria. They are the site of the light-dependent reactions of photosynthesis.

List required macronutrients.

List required micronutrients.

________is growth of a pure culture.

What are prototrophic bacteria?

What are Auxotrophic bacteria?

What is cellular communication based on cell density and nutrients.

_______is the destruction of all cells, viruses, and spores.

_______is the reduction of pathogen numbers for inanimate objects.

_________is the reduction of pathogen numbers for living tissues.

______is basic hygenic practices.

Define bacteriostatic

Define bacteriocidal

Define bacteriolytic.