ch27 Flashcards
Choose the list below that contains the substances required by typical nitrogen-fixing cyanobacteria.
Carbon dioxide, nitrogen, water, light, and some minerals
Bacteria that __________ tend to have abundant internal membranes.
are photosynthetic
Which of the following is a structure that bacteria, archaea, and eukaryotes have?
Plasma membrane
Which group of bacteria is unusual in that they lack peptidoglycan in their cell walls?
Chlamydias
The Desulfovibrio bacterium breaks down organic matter (which it must have) and uses sulfate (not oxygen) as an electron acceptor. As a result, it produces hydrogen sulfide (H2S), accounting for the “rotten egg” smell of swamp muck. Oxygen is a deadly poison to Desulfovibrio.
We would call Desulfovibrio a(n) __________.
obligately anaerobic chemoheterotroph
Which subgroup of proteobacteria contains many species that are closely associated with eukaryotic hosts in mutualistic or parasitic relationships?
Alpha
What is the function of a bacterial endospore?
To facilitate persistence in temporarily harsh environments
Bacteria that use light for their energy source and CO2 for their carbon source are called __________.
photoautotrophs
An F+ bacterial cell __________.
acts as a donor during conjugation
What is a difference between the cell walls of prokaryotes and the cell walls of eukaryotes?
The cell walls of prokaryotes are made of molecules different from those comprising the cell walls of eukaryotes.
What is the structural feature of gram-positive bacteria that results in their retaining a crystal violet dye stain and thereby being distinguished from gram-negative bacteria in a Gram-stain technique?
Gram-positive bacteria have thicker cell walls.
Portions of the genomes of certain prokaryotic species are very similar to portions of the genomes of distantly related prokaryotes. The process that most likely accounts for this genetic similarity is __________.
horizontal gene transfer
Antibiotics administered in human medicine work against bacterial infections by __________.
interfering with an aspect of bacterial metabolism or structure that differs from that of eukaryotic cells
Acquiring an R plasmid would allow a bacterium to do what?
Resist antibiotics
Some prokaryotes stick to their substrate or to one another by means of hairlike appendages, each called a __________.
fimbria
In an experiment, a microbiologist put equal numbers of each of the following organisms into a flask of sterile broth, consisting mostly of sugar and a few amino acids. She then placed the flask in the dark.
Which of the following organisms would be most likely to survive?
Chemoheterotrophic bacteria
Which of the following is not a true statement concerning bacterial flagella?
Bacterial flagella are homologous to the flagella of eukaryotic cells.
Bacterial flagella have a very complex structure composed of 42 distinct proteins. What is the most likely explanation for the evolution of these complex structures?
Exaptation
Why is salt a good preservative to use for foods such as pork and fish?
Prokaryotic cells living in the food will shrink from their cell walls, impacting their ability to reproduce.
Which of the following is not one of the most common prokaryotic cell shapes?
Cuboidal
Which subgroup of proteobacteria contains many species that are predators of other bacteria?
Delta
Which of the following is a disease caused by bacteria?
Tuberculosis
Prokaryotes found inhabiting the Great Salt Lake would be __________.
extreme halophiles
Which of the following does not contribute to bacteria’s ability to evolve rapidly?
Sexual reproduction
