Unit 2 - Ch. 11
A group of Gram-negative bacteria has a spiral shape and a unique motility mechanism that allows them to move through thick, viscous substances. This group is called the _______
spirochetes
Scientists are interested in studying the growth of extreme _______, archaea that grow near volcanic vents and fissures because these conditions are thought to mimic early earth's environment
thermophiles
Bacteria that oxidize sulfur are Gram-negative rods or spirals that
use sulfur compounds as an energy source and oxygen as a terminal electron acceptor
Aerobic chemolithotrophs obtain energy by oxidizing reduced inorganic chemicals, using ______ as a terminal electron acceptor
oxygen
Aerobic chemolithotrophs obtain energy by oxidizing reduced inorganic chemicals, using ________ as a terminal electron acceptor
oxygen
Ecophysiology is the study of the _______
physiological mechanisms bacteria and archaea use to live in terrestrial and aquatic environments
Bdellovibrio species ______
prey on Gram negative bacteria like E. coli bore a hole in the cell wall of their prey are highly motile Gram-negative curved rods
Cyanobacteria as a group are capable of ______
both photosynthesis and nitrogen fixation
How do aerobic chemoorganotrophs obtain their energy?
by oxidizing organic compounds by using O2 as a terminal electron acceptor
The _______ bacteria have projections called prosthecae, which are extensions of the cytoplasm and cell wall that increase the surface area to facilitate absorption of nutrients
prosthecate
As a group, anaerobic chemoorganotrophs ______
can obtain energy via fermentation produce ATP via substrate level phosphorylation
The cells of species in the genus Neisseria are ______
cocci Gram-negative typically found in pairs
The purpose of the sheath in sheathed bacteria is for _______
protection
The purple bacteria are Gram-negative organisms that can appear ______ due to their light-harvesting pigments
red, orange, & purple
The study of the various adaptations prokaryotes use to survive terrestrial and aquatic environments is called
ecophysiology
Of the various types of dormant cells, the ______ is the most resistant to environmental extremes
endospore
In this micrograph of stained bacterial cells, the structures forming in the mid-portion of the cells are called _______
endospores
Prosthecate bacteria form projections called prosthecae, which are extensions of the cytoplasm and cell wall. These prosthecae ______
facilitate absorption of nutrients
Obligate aerobes obtain energy using ________ exclusively; none of them can ferment
respiration
An anaerobic chemoorganotroph that uses glucose for energy and pyruvate as its terminal electron acceptor is performing _______
fermentation
Prokaryotes that grow well in an environment that contains 32% NaCl would be called extreme ______
halophiles
_______ species are Gram-negative curved rods that are highly motile and prey on other Gram-negative rods by boring a hole in their cell wall
Bdellovibrio
A group of bacteria called green bacteria are _______
Gram-negative
Members of the family Enterobacteriaceae are ________
Gram-negative rods
Which of the following genera of organisms forms a beneficial symbiotic relationship with plants?
Rhizobium
An organism that cannot reproduce outside of a host cell is termed an ______ ______ parasite
obligate intracellular
Nitrifiers can be described as bacteria that _______
obtain energy by oxidizing inorganic nitrogen compounds such as ammonium or nitrite; are Gram-negative
Chemoorganotrophs oxidize _______ compounds such as glucose to obtain energy
organic
Aerobic chemoorganotrophs gain energy via the ________, using O2 as a terminal electron acceptor
oxidation of organic compounds
How do obligate aerobes obtain energy?
using respiration only
Extreme thermophiles are found near ______
volcanic vents hot springs hydrothermal vents
Oxygenic phototrophs use ______ as a source of electrons for reducing power, generating O2
water
Hydrogen-oxidizing bacteria such as Aquifex and Hydrogenobacter are ______
Gram-negative, thermophilic, & obligate chemolithotrophs
Spirochetes are bacteria that are ______ and possess a unique mechanism of _______
Gram-negative; motility
Aside from green and purple bacteria, Gram-positive endospore forming rods of the genus _______ are also anoxygenic phototrophs
Heliobacterium
Which of the following correctly describe relationships between genera of bacteria and their means for obtaining nutrients from plants?
Rhizobium species form a mutually beneficial relationship with certain types of plants Agrobacterium species are plant pathogens that cause tumor-like growths
Cyanobacteria as a group are capable of _______
both photosynthesis and nitrogen fixation
Sulfur-oxidizing bacteria ______
can use hydrogen sulfide or thiosulfate as an energy source can sometimes grow in filaments
The earliest oxygenic phototrophs probably belonged to a group of bacteria called the _______
cyanobacteria
Unlike in other anoxygenic phototrophs, in purple bacteria, the components of the photosynthetic apparatus are all located in the cell's ________ membrane
cytoplasmic
An organism that requires a minimum of 9% NaCl would be called an extreme ______
halophile
By definition, obligate intracellular parasites cannot ______
replicate outside of a host cell
Staphylococcus epidermidis is part of the normal microbiota of the _______
skin
In a healthy individual, anaerobes can regularly be found on and in the _______
skin, oral cavity, and intestinal tract
The motile cells found in sheathed bacteria are called ______ cells, and these exit through the end of the sheath
swarmer
______ species are Gram-negative, strictly anaerobic, make up about a third of the bacteria in fecal matter in humans, and are associated with abscesses and bloodstream infections
Bacteroides
True or false: Scientists now understand the true diversity of microbial life and have determined the relationships between the millions of prokaryotes that exist
False
During photosynthesis, anoxygenic phototrophs use _______ as a source of electrons to make reducing power
H2S
A reason why environments that are routinely exposed to O2 can support anaerobic growth is that _______
O2-consuming organisms depletes the oxygen levels
I say: "Gram-negative bacteria, that are typically kidney-bean-shaped cocci in pairs. You say:
"Neisseria"
_______ gain energy via the oxidation of reduced inorganic chemicals, using O2 as a terminal electron acceptor
Aerobic chemolithotrophs
Characterized members of the domain _______ typically thrive in extreme environments, such as high heat, acidity, alkalinity, and salinity
Archaea
The purpose of storage granules produced by some bacteria is to store ______
nutrients
Which of the following bacteria is typically a harmless resident of the skin?
Staphylococcus epidermidis
Organisms that form storage granules include ______
Thioploca Thiomargarita Spirillum
Which of the following statements about microbial diversity is true?
We are only now beginning to understand the diversity of prokaryotes
Chemoorganotrophs that perform _______ often use sulfur or sulfate as a terminal electron acceptor
anaerobic respiration
Which of the following were likely the earliest photosynthesizing organisms?
anoxygenic phototrophs
An organism found in an environment that is very hot and acidic is most likely a member of the domain ______
archaea
Most of the anaerobic chemolithotrophs that have been discovered are members of what domain?
archaea
Members of the Gram-negative genera Aquifex and Hydrogenobacter are hydrogen-oxidizing bacteria. An example of their metabolism involves using ________
hydrogen as a source of energy and oxygen as a terminal electron acceptor, forming water
Enterobacteriaceae get their name because they reside in the ______ tract of humans and animals
intestinal
The normal habitat of Bacteroides species in humans includes the ______
mouth intestines genital tract
The green bacteria are Gram-______ organisms that are typically green or brownish in color
negative
A diverse group of Gram-negative bacteria that obtain energy by oxidizing inorganic nitrogen compounds such as ammonium or nitrate are known as _______
nitrifiers
A diverse group of Gram-negative bacteria that obtain energy by oxidizing inorganic nitrogen compounds such as ammonium or nitrate are known as ________
nitrifiers
Many cyanobacteria can convert nitrogen gas (N2) to ammonia, which is a process called ______
nitrogen fixation
As a group, chemolithotrophs _______ to obtain energy
oxidize reduced inorganic chemicals such as hydrogen gas
Like the green and purple bacteria, members of the genus Heliobacterium are also examples of anoxygenic phototrophs. They are _______ bacteria related to members of the genus Clostridium
rod-shaped, Gram-positive, & endospore-forming