Chapter 4 Quiz+

Cyanobacteria are an example of A. photoheterotrophs. B. photoautotrophs. C. chemoheterotrophs. D. chemoautotrophs.

photoautotrophs

Coupled transport to move nutrients into the cell against their concentration gradients is most likely to occur along with the electrical gradient of A. positive ions into the cell. B. positive ions out of the cell. C. negative ions inside the cell. D. water.

positive ions into the cell

Which of the following statements is true? A. Most bacterial species can be cultured in the lab. B. All bacterial species require the same essential nutrients. C. All organisms require carbon as a macronutrient. D. Bacterial species use a limited number of nutrient sources.

All organisms require carbon as a macronutrient

Which of the following is true? A. Bacteria can undergo cell differentiation in response to an environmental stress. B. Bacteria can undergo cell differentiation without a change in gene expression. C. Only eukaryotes, and not prokaryotes, can undergo cell differentiation. D. Bacterial cell differentiation only produces small changes in morphology.

bacteria can undergo cell differentiation in response to an environmental stress

Which of the following is true of complex media? A. Bacteria grow faster on them than on synthetic media B. All the components and their concentrations are known. C. Complex media are the most difficult of all to prepare. D. Complex media can help determine the metabolic capacity of an organism.

bacteria grow faster on them than on synthetic media

An essential nutrient is one that A. bacteria need for proper growth and can make themselves. B. bacteria need for proper growth and cannot make themselves. C. is not needed by the bacteria for proper growth. D. is always plentiful in the environment.

bacteria need for proper growth and cannot make themselves

The ABC transporters A. are represented by only a handful of proteins. B. are located on the outer membrane in gram-negative bacteria. C. bind ATP on the intracellular side of the cell membrane. D. are only involved in nutrient influx.

bind ATP on the intracellular side of the cell membrane

Nitrogen-fixing bacteria A. can convert atmospheric nitrogen into ammonia. B. are all symbionts with legumes. C. are all found in the ocean. D. are not involved in the nitrogen cycle.

can convert atmospheric nitrogen into ammonia

With respect to counting cells, a "viable" bacterium is one that A. can replicate and form a colony on a solid media surface. B. consumes oxygen via aerobic respiration. C. can scatter light and be detected by optical density. D. is capable of being infected by a bacteriophage.

can replicate and form a colony on a solid media surface

Which of the following is true of cells in batch culture? A. Cells never reach exponential growth rates. B. Metabolic wastes do not accumulate. C. Cells will not remain at a constant mass. D. New batches of media are added during culture.

cells will not remain at a constant mass

Some bacteria live in deep sea vents where no light penetrates, yet are still capable of producing their own reduced carbon. These organisms are classified as A. photoheterotrophs B. chemoautotrophs C. chemoheterotrophs D. photoautotrophs

chemoautotrophs

Suppose you want to isolate E. coli mutants incapable of synthesizing the amino acid arginine. You grow mutagenized bacteria on a master plate of complete media and make a replica plate (by pressing a velvet block onto the master plate and then pressing it onto the replica plate-bacteria will be transferred) on media lacking arginine. Colonies that grew on the master plate but not the replica plate are arginine synthesizing mutants. In this example, the replica plate A. is a liquid media culture condition. B. contains selective media. C. contains differential media. D. contains complex media.

contains selective media

Which of the following is not a macronutrient? A. carbon B. phosphorus C. copper D. oxygen

copper

Which of the following nutrients would you need to add the least of to a culture medium? A. zinc B. magnesium C. nitrogen D. phosphorous

zinc

If a bacterium can divide once an hour, after 5 hours, 1 bacterium will yield A. 5 bacteria. B. 10 bacteria. C. 32 bacteria. D. 50 bacteria.

32 bacteria

If an organism has a mean growth rate constant (k) of 1/hour, then the mean generation time, g, is A. 30 minutes. B. 60 minutes. C. 120 minutes. D. impossible to determine.

60 minutes

If 1 ml of a 10-4 dilution of a cell culture yields 98 colonies on an agar plate, how many colony-forming units/ml are there in the original culture? A. 98 B. 9800 C. 9.8 x 10^4 D. 9.8 x 10^5

9.8 x 10^5

You incubate cells with propidium iodide and then visualize under a fluorescence microscope. About 50% of the cells fluoresce red, indicating uptake of propidium iodide. Your conclusion from this result is that A. about half the cells were eating during the incubation time and ingested propidium iodide. B. about half the cells are alive. C. each cell has a random, 50-50 chance of staining with propidium iodide. D. you are unable to draw any conclusions.

about half the cells are alive

Scientists study microbial growth because A. learning what makes bacteria grow can lead insights on how to prevent their growth. B. many microbes are used for commercial, industrial purposes. C. microbes can serve as model organisms for fundamental biological processes. D. all of the above

all of the above

A bacterium produces a toxic metabolic by-product that it needs to efflux to the environment against the toxin's concentration gradient. The energy to drive this efflux comes from the electrochemically favorable influx of protons. This is an example of A. ABC transport B. antiport C. symport D. facilitated diffusion

antiport

You discover a new E. coli permease that moves an uncharged sugar into the cell along with a proton. This new permease can be classified as an A. electrogenic symporter. B. electrogenic antiporter. C. electroneutral symporter. D. electroneutral antiporter.

electrogenic symporter

Which of the following is true of endospores? A. All bacterial species can produce endospores. B. Endospores are produced from vegetative cells when nutrients are abundant. C. Endospores are resistant to many stresses that would kill vegetative cells. D. Endospores can only germinate into viable vegetative cells within 10 years.

endospores are resistant to many stresses that would kill vegetative cells

Under optimal conditions one E. coli cell can become two cells A. every 2 to 3 minutes. B. every 20 to 30 minutes. C. every 2 to 3 hours. D. every 2 to 3 days.

every 20 to 30 minutes

One method to count only cells that express a particular protein on their cell surface is A. the coulter counter. B. fluorescent activated cell sorting (FACS). C. direct counting with a microscope. D. colony formation counts.

fluorescent activated cell sorting (FACS)

A medium containing bile salts and crystal violet selects for growth against A. all bacteria. B. bacteria that cannot ferment lactose. C. Gram-positive bacteria. D. Gram-negative bacteria.

gram-positive bacteria

Organisms that need to ingest reduced carbon are called A. heterotrophs. B. autotrophs. C. lithotrophs. D. phototrophs.

heterotrophs

If the E1 enzyme of the phosphotransferase system (PTS ) was nonfunctional, which of the following would be a consequence? A. PTS mediated import of glucose would stop, but other sugars using the PTS system would continue to be imported. B. The histidine-rich protein, PtsH, would show increased phosphorylation levels. C. The cell would grow at a faster rate because E1 would not be removing a phosphate from phosphoenol pyruvate. D. Import of all substrates dependent on the PTS system would eventually stop.

import of all substrates dependent on the PTS system would eventually stop

Siderophores are responsible for helping bacteria acquire A. iron. B. ammonium ion. C. phosphorus. D. calcium.

iron

Which of the following is NOT true of the phosphotransferase system? A. It requires energy expenditure. B. It is an example of an ABC transporter. C. It contains both cytoplasmic and cell membrane components. D. It transfers a phosphate group to sugar.

it is an example of an ABC transporter

The correct order of phases for bacteria inoculated into a new culture medium is A. stationary, log, lag, death. B. log, lag, stationary, death. C. lag, log, stationary, death. D. lag, stationary, log, death.

lag, log, stationary, death

Biofilms A. are flat, two-dimensional films of bacteria. B. contain only a single species of bacteria. C. are relatively rare. D. may cause health problems for humans.

may cause health problems for humans

For a bacterium to uptake glucose against its concentration gradient A. is simple because glucose can directly cross the plasma membrane. B. means the bacterium will require a glucose transport protein but no energy expenditure. C. means the bacterium will require a glucose transport protein and will also expend energy. D. is impossible because a bacterium cannot accumulate a nutrient at a higher concentration inside the cell than is present in the environment.

means that the bacterium will require a glucose transport protein and will also expend energy

A continuous culture differs from a batch culture because in continuous culture, A. the temperature is held constant. B. the flask is continuously shaken. C. the temperature continuously increases. D. new media is added and old media removed.

new media is added and old media removed

The heterocyst cells of cyanobacteria are specialized for A. photosynthesis. B. nitrogen fixation. C. gliding motility. D. antibiotic production.

nitrogen fixation

Nitrogen fixation is the conversion of A. ammonium ion to nitrogen gas. B. ammonium ion to nitrate ion. C. nitrate ion to nitrogen gas. D. nitrogen gas to ammonium ion.

nitrogen gas to ammonium ion