Chapter 19 Microbial Ecosystems,100% CORRECT

Which metric describes the proportion of EACH species present in a community? A) species abundance B) species diversity C) species evenness D) species richness 2) Which of the following represents increasing microbial diversity? A) guild-community-population B) population-guild-community C) cell-community-population D) community-guild-population 3) The abundance of cyanobacterial mats has greatly declined due to the evolution of A) antimicrobial-producing fungi. B) bacteriophages. C) metazoan grazers. D) Proteobacteria. 4) A notorious biofilm former implicated in cystic fibrosis is A) Bacillus subtilis. B) Escherichia coli. C) Lactobacillus acidophilus. D) Pseudomonas aeruginosa. 5) Some nitrifying prokaryotes carry out metabolic cooperation by a process known as A) competition. B) niche partitioning. C) syntrophy. D) antagonism. 6) The generation time of Escherichia coli in the human intestine is ________ in laboratory culture. A) at about the same rate as B) faster than C) more optimal than D) slower than 7) In a stratified lake, the warmer and less dense layer is called the A) epilimnion. B) hypolimnion. C) hyperlimnion. D) thermocline. 8) The photosynthetic pigments bacteriorhodopsin and proteorhodopsin are present in ________ and ________, respectively. A) Archaea / Bacteria B) Bacteria / Archaea C) Bacteria / Bacteria D) Bacteria / Eukarya 9) Microenvironments of soil exist where ________ concentrations greatly vary. A) oxygen B) nitrate C) sulfur D) oxygen, nitrate, and sulfur 10) The emergence of new microbial species because of geographic isolation is called ________ speciation. A) allopatric B) biogeochemical C) biogeological D) isolatory 11) Which of the following can function as intracellular signaling molecules? A) acylated homoserine lactones B) hydrophilic lipids C) quinones D) proteorhodopsins 12) Which metabolic strategy is MOST common in chemolithotrophic mats? A) ammonia oxidation B) iron oxidation C) nitrate reduction D) sulfur oxidation 13) During periods of stratification, transfer between surface and bottom waters is controlled by A) mixing. B) diffusion. C) niche partitioning. D) current. 14) Assuming exposure to the same climate, which of the following aquatic systems would be MOST stratified? A) 20 m deep freshwater river B) 50 m deep marine water fjord C) 200 m deep saltwater lake D) 300 m deep freshwater lake 15) Which is the CORRECT order of increasing size in soil particles? A) clay sand silt B) clay silt sand C) sand clay silt D) silt clay sand 16) A soil that lacks a dominate particle size is referred to as a(n) A) aggregation. B) bisequum. C) loam. D) mottled soil. 17) According to bacterial abundance studies done so far on soils, the ________ represent the most abundant phylum. A) Proteobacteria B) Acidobacteria C) Actinobacteria D) Firmicutes 18) Which bacterial genus is responsible for producing ferrous iron (Fe2+) in groundwater? A) Alteromonas B) Aquifex C) Geobacter D) Loktanella 19) An organism living in the bottommost region of a body of water is described as being A) benthic. B) litoral. C) neritic. D) pelagic. 20) The chemical oxygen demand (COD) of a body of water is determined using a(n) A) microelectrode. B) oxygenator. C) spectrophotometer to determine the OD540nm. D) strong oxidizing agent. 21) Which aquatic habitat contains a pelagic zone? A) estuary B) lake C) salt marsh D) open ocean 22) Which are the MOST dominant chemolithotrophs in pelagic waters? A) ammonia-oxidizing Archaea B) ammonia-oxidizing Bacteria C) sulfate-reducing Bacteria D) Prochlorococcus 23) From the aquatic systems below, where are heterotrophic Bacteria the MOST abundant? A) coastal waters B) deep sea C) Sargasso Sea D) open ocean 24) All Prochlorococcus strains contain A) chlorophylls a and b. B) chlorophyll a and phycobilins. C) chlorophyll b and phycobilins. D) chlorophylls a and b and phycobilins. 25) Which of the following is NOT an oxygenic phototrophic microorganism present in marine waters? A) Ostreococcus B) Prochlorococcus C) Roseobacter D) Trichodesmium 26) What is an average concentration of prokaryotic cells along the surface of pelagic water? A) 104 cells/ml B) 106 cells/ml C) 108 cells/ml D) 1010 cells/ml 27) Epsilonproteobacteria are most dominant in hydrothermal vents because they A) reduce nitrogen. B) oxidize reduced sulfur compounds. C) use oxygen as electron acceptors. D) bind divalent cations. 28) Archaea in pelagic deep-water are almost exclusively A) Crenarchaeota. B) Euryarchaeota. C) Nanoarchaeota. D) Thaumarchaeota. 29) Shallow marine sediments are dominated by A) Firmicutes. B) Planctomycetes. C) Proteobacteria. D) Tenericutes. 30) Which statement is TRUE about the fluid from the hydrothermal vents? A) The fluid contains large amounts of oxidized inorganic materials. B) The fluid contains large amounts of reduced inorganic materials. C) The fluid contains large amounts of organic material. D) The fluid usually contains about equal amounts of organic and inorganic material. 31) The primary metal sulfides emitted from the black smokers are ________ sulfides. A) copper B) iron C) magnesium D) zinc 32) What adaptation do organisms have that tolerate high pressures? A) decreased cell size B) decreased lipid content C) increased ribosome size D) increased unsaturated fatty acids 33) A chemical that comes from outside the ecosystem is referred to as a(n) ________ chemical. A) synthropic B) lithotrophic C) allochthonous D) pleomorphic 34) Ecological theory states that for every organism there is at LEAST one ________, and the microenvironment where the organism is MOST successful is called the ________. A) population / community B) niche / prime niche C) prime niche / niche D) community / population 35) A population of metabolically related microorganisms is called a(n) A) guild. B) niche. C) ecosystem. D) haplotype. 36) Which of the following an example of a biofilm? A) soap scum B) dental plaque C) marine diatom D) planktonic microcolony 37) Sedimentation in bogs and marshes develop ________ soils. A) inorganic B) mineral C) organic D) loamy 38) The number of Roseobacter in the ocean describes A) species diversity. B) species richness. C) species abundance. D) species prevalence. 39) ________ are the main primary producers in freshwater environments. A) Phototrophic microorganisms B) Heterotrophic microorganisms C) Chemolithotrophic microorganisms D) Viral microorganisms 40) Sudden nutrient perturbations in an environment generally ________ the overall prokaryotic diversity. A) increase B) decrease C) maintain D) replicate 41) Water in the rocks and soils of Earth's subsurface is called A) groundwater. B) surface water. C) subsurface water. D) deep water. 42) The microbial oxygen-consuming capacity of a water sample is called its A) chemical oxygen demand. B) biochemical capacity. C) biochemical oxygen demand. D) chemical capacity. 43) Two major environmental extremes of the deep sea are high ________ and low ________. A) pressure / nutrient levels B) nutrient levels / pressure C) temperature / pressure D) oxygen / pressure 44) Biomass generation due to heterotrophic organisms is called ________ production. A) primary B) secondary C) auxotrophic D) regulatory 45) In the oceans, prokaryotes are outnumbered ten to one by A) zooplankton. B) diatoms. C) viruses. D) phytoplankton. 46) ________ use inorganic electron donors released from deep-sea hydrothermal vents. A) Chemolithotrophs B) Photoheterotrophs C) Chemoheterotrophs D) Photolithotrophs 47) Cells within a biofilm excrete an adhesive matrix primarily composed of ________ but can also contain nucleic acids as well as proteins. A) lipids B) fatty acids C) monomers D) polysaccharides 48) Cyclic dimeric guanosine monophosphate (c-di-GMP) serves as a messenger molecule in bacterial cells to coordinate a shift from ________ to ________ growth. A) sessile / planktonic B) planktonic / sessile C) monomorphic / polymorphic D) stationary / exponential 49) The most abundant prokaryotic organism in the ocean is of the ________ genus. A) Pelagibacter B) Puniceispirillum C) Roseobacter D) Prochlorococcus True/False Questions 1) An ecosystem includes both the living organisms and abiotic materials that function together. 2) Many microbial habitats are unsuitable for plants and animals. 3) The physiochemical conditions of a microenvironment, by definition, remain static. 4) A microbial population can contain several microbial communities. 5) Chemoheterotrophic bacteria are primary producers. 6) Cyclic di-guanosine monophosphate is upregulated as Pseudomonas aeruginosa cells are declining. 7) Arid soils are among the most extreme environments on earth. 8) Due to such an array of nutrients, microorganisms are often capable of sustaining exponential growth in the environment. 9) The cells within a biofilm can undergo intra-species signaling; however, inter-species signaling does not occur. 10) Mineral soils largely come from weathered limestone and sand. 11) The formation of soil involves a combination of biological, chemical, and physical processes. 12) Soil particles are classified based on their size. 13) Chemoorganotrophic bacteria can facilitate the formation of soil through the secretion of organic acids. 14) Limiting nutrients in soils are generally organic compounds. 15) Functional differences can be observed by using 16S rRNA gene phylogenetics of a microbial community. 16) Microbial life has been identified at depths of 3 km despite being anoxic. 17) ALL stratified lakes contain a thermocline. 18) Gammaproteobacteria can be used for biodegradation of hydrocarbons. 19) In many marine systems, the carbon and oxygen cycles are directly proportional to each other. 20) Low return of nutrients in the pelagic zone results in relatively low primary production in the open ocean when compared to freshwater lake systems. 21) Unlike other cyanobacteria, Prochlorococcus lacks phycobilins. 22) Purple phototrophic bacteria that use bacteriochlorophyll a are oxygenic. 23) Archaea and Bacteria dominate the upper 100 m of the open ocean while viruses dominate depths greater than 100 m. 24) Oligotrophic organisms do NOT grow well under nutrient-replete conditions. 25) In the context of nutrients, a sink is one that slowly releases a particular nutrient over time. Essay Questions 1) Explain three reasons why bacteria form biofilms. 2) Distinguish an ecotype from a species, and provide an example of an ecotype. 3) What is the difference between an organism being piezophilic and piezotolerant? 4) Describe three molecular effects high pressure has on the physiology of organisms. 5) Provide a reason for the ecological importance of pelagic Bacteria and Archaea. 6) Explain how both biochemical oxygen demand and chemical oxygen demand are measured. 7) Describe two roles viruses have in the open ocean. 8) What advantage do proteorhodopsin-containing organisms have over other heterotrophic microbes in the open ocean? 9) Explain why biofilms are a concern in medicine. 10) Describe four environmental conditions that would likely change the relative abundances of the members within a microbial community.