ch. 25 bacteria & archea
cows and other ruminates rely on a ______ relationship with bacteria in their digestive tract
mutalistic
which type of bacterium would not be able to survive in the presence of oxygen
obligate anaerobic
in transduction, two prokaryotic cells of different mating types come together and genetic material is transferred from one cell to another
false- conjugation
what are the small circles of DNA that exist within the bacterial cytoplasm in addition to the bacterial chromosome
plasmids
gram-positive bacteria would stain ______ in a gram stain because of a thick layer of _______
purple, peptidoglycan
bacilli
rod shaped bacteria
These statements about bacteria are true
some bacteria can photosynthesize, bacteria are important decomposers, a small % of bacteria are pathogenic, and bacteria convert atmospheric nitrogen into ammonia and then nitrates that can be used by plants
peptidoglycan consists of
sugars cross-linked with proteins
list the characteristics of archaea and bacteria
in contrast to bacteria, archaea do not have peptidoglycan in their cell walls. both archaea and bacteria lack the membrane organelles of eukarya
compare and contrast obligate anaerobes, facultative anaerobes, and aerobes
obligate anaerobes cannot metabolize in the presence of oxygen, facultative anaerobes can metabolize with or without the presence of oxygen, aerobes can only metabolize in the presence of oxygen
some bacteria avoid being phagocytized by a host's immune system by means of
their capsule
plasmids of bacteria often have genes involved in
antibiotic resistance
the most significant difference between archaea and bacteria is the
absence of peptidoglycans in the cell walls of the archaea
compare and contrast autotrophic and heterotrophic bacteria
autotrophic bacteria make their own organic compounds from inorganic sources. heterotrophic bacteria must obtain their carbon compounds from the organic compounds produced by other organisms
how do some bacteria respond to adverse environmental conditions
bacteria form endospores
the most common mode of reproduction in bacteria is
binary fission
how do bacteria move
by means of a rotating flagella
prokaryotes have a nucleus that contains DNA
false
_____ is a form of genetic exchange in bacteria that involves contact between two cells
conjugation
which is the only prokaryote to carry on photosynthesis that generates oxygen
cyanobacteria
what is the purpose of sex pili?
to transmit DNA between bacteria
bacterial plasmids often have genes that code for genetic exchange or antibiotic resistance
true
the dense cytoplasm of the prokaryote contains ribosomes and storage granules
true
